Earth Worm Dissection

Here is the anatomy of an earthworm, click to enlarge.

On a less serious note Reproduction!

Which leads to cocoons!  

 

Now about dissecting the worm....Watch the video!

Life on Earth Video Warning! 10 Minutes

Life on Earth Con.

• Small changes is evolution
• all systems evole together 
• heart is pump in open and closed
• all cells have to be surrounded by water
• animals started running faster and needed more oxygen
• Amphibian-cold blooded, not very big or active, heart works well-3 chambers
• Four chambers-Birds and mammals
• Veins can grow-cells do not fit together
• Lymphatic system-lymph baths every cell-lymph tissue=blood plasma
• We developed from protists
• Small animals could breather through skin
• Gills evolved early on, not only fish have
• Tracheal tubes have spiracles in insect
• Gases exchanged rapidly, lungs inflate gills
• Air pushs over gills which are extensions of blood vessels
• Lungs have branches with air sacs called the Alvelus
• Branched allows for more surface area to be covered
• Excretory Systems
• Chyme is thrown up food, which the somach adds water to
• Digestion chemically rots food
• Villi increase the surface area, they are filled with blood vessels
• Large intestine absorbs water
• Diffusion=microorganism
• Flame cells fill u and contract moving waste to a excretory tubule
• Malpighian tubes-Kidneys, extract waste
• Nephridia serve the same functions because they are kidneys

Life on Earth

Here are some class notes from this week,

• We have muscle tissue and nervous tissue 
• We take in resources (food) then process, then synthesize and eliminate it
• Early lifeforms digest on inside
• Takes food in gizzard, transports, and then eliminates
• All life has that in common, anatomy and physiology
• one celled protists~not animal; fungus or plant
• It can achieve all of this because it lives in H2O
• Sponge has cells that are all in contact with H2O
• They cannot eat because they do not have mouths.
• Cridenians->hydras, corals,->hunt,process...ect
• Extracellular digestion->out of cell in stomach
• Tube within a tube, lines levels of complexity
• Compartalization~digest different things
• From aquatic~to terrestial we needed support.
• Chordata-all animals with abackbone
• You need breathing apparatus
• Need to be able to sense, sense organs->brain, eyes, ect..
• We still have our reptile brain
• Open pumps blood through vessels, many hearts, short life span, and just randomly moves around
• Closed circulatory systems have veins which are better, faster and warmer. Veins move the blood faster.
• Body Symmetry-Amorphic->Sponges, Radial Symmetry->Starfish, Bilateral->cuts at one spot.
• Circulatory-->
• 2 chambered heart-Arteries away from heart-fish
• When they blend~amphibian=O2 rich and O2 poor blood mix
• You're breathing just like a one celled creature, it never changes its just made things more complex.
• Eat=mouth, or can be observed (sponge)
• Process=sack (hydra) stomach or vacoules
• Synthesize= Endoplasmic R., large intestine, or just a digestive system
• Eliminate=back through mouth (hydra), an anus, or a vacoule like object called the anal pore 

Cladogram and Dichotomous Key

Cladists group organisms based on shared derived characters, not the overall similarity of potential group members.



Dichotomous keys are the most common keys encountered. They may be laid out in various ways, but usually form a series of numbered questions arranged in “couplets” as shown below:

1. Bark on trunk smooth .......................... 2
Bark on trunk rough ............................ 3

2. Bark mostly white ............................... 4
Bark other colours .............................. 7
Each time a question is answered, the user is directed to the number of a new question-couplet. This continues until, instead of a number, the name of the species (or other taxon) is given. This type of key is called a “dichotomous” key because the meaning of the word is "two branching", although in practice dichotomous keys often have questions with more than two choices. The structure of the key is such that each question is actually like a tree branch that has smaller branches proceeding from it, as demonstrated below for keying out four "egg-laying animals".

Short Video on Evidence for Evolution

Evolution Themed Notes

Abiogenesis, or origin of life, is the study of how life on Earth emerged from inanimate organic and inorganic molecules.

Biogenesis is the process of lifeforms producing other lifeforms.

Similar embryos- common ancestor

Homologous structures- similar structures

Competition has to exist for evolution to occur

To survive a species needs to fill niches and decrease competition

Evolution- Tree of life

Sympatric- Speciation within a population

Allopatric- Isolated population's speciation

Parapatric- Speciation two populations barely overlap 

Allopatric is the fastest while sympatric is the slowest form of evolution

Stabilizing selection- culls extreme variants from the population

Directional selection- shifts the overall makeup of a population

Diversifying selection- favors variants of opposite extremes over intermediate individuals

Gradual change- Even change over life, not many changes, and little evolution occurs

Divergent Evolution- Started the same, but is experiencing a different environment and different pressures

Adaptive Radiation or niche- Different ways of life (Founder effect), needed to survive

Convergent evolution- Coming together from a common ancestor

Finally Gradualism- gradual change

Punctuated Equilibrium- rapid change causes change in organisms immediately

Bottleneck effect- diversity->event->a few surviving population

Kingdom Video

The Classification System

The Classification System

Taxonomists group living things into a hierarchy that moves from general to specific. Organisms found in the same Kingdom are related, but not closely related. Presently, scientists accept that there are five Kingdoms of living organisms: Animalia, Plantae, Protoctista, Fungi, and Monera. The Animalia, Plantae, Fungi and Protoctista are part of the Domain Eukarya. The Kingdom Monera contains two Domains: the Eubacteria and Archea. Currently, there is some of debate among scientists with respect to the Kingdom level of classification because the use of DNA-based technology has allowed us to look more closely at the genetic relationships between organisms.

Each Kingdom is divided into smaller groups called Phyla (singular Phylum) that contain more closely related organisms. Each Phylum, in turn, is subdivided into smaller groups called Classes. A Class is composed of many Orders, which contain a number of Families. A Family of living things is made up of Genera (singular Genus). Finally, each Genus is divided into the smallest and most closely related group of organisms called the species.

The smallest grouping in the taxonomy hierarchy is the species, which contains organisms that are very closely related. In order to be classified in the same species, the organisms must be able to produce viable (fertile) offspring. The species level is the most reliable and useful to scientists.

The following diagram illustrates the taxonomic relationships accepted by many scientists today:

Classification

Classification 

As a result of the confusion using common names, scientists have designed a system to classify or group living organisms. Today, the modern science of grouping living things is called Taxonomy. Taxonomists put all living things into arbitrarily selected groupings or categories that lump the organisms together with other living things based on:

• Structural similarities and differences
• Genetic similarities and differences
• Biochemical similarities and differences
• Cellular organization
• Evidence from evolutionary relationships

Hardy-Weinberg

The Hardy-Weinberg Theorem states that the allele frequencies of a gene in a population will remain constant, as long as evolutionary forces are not acting. H-W therefore provides a baseline (a null expectation) for a population that is not evolving. For a population to be in H-W equilibrium, the following conditions or assumptions must be met:

1. The population is very large; there is no genetic drift
2. Matings are random
3. There is no mutation
4. There is no migration
5. There is no selection

If one of these conditions is broken, an evolutionary force is acting to change allele frequencies, and the population may not be in H-W equilibrium. Natural populations probably seldom meet all of these conditions; H-W provides a nice model to study evolution via deviations from H-W equilibrium.

Hardy Weinberg Equation

Basic Relations

A = dominant allele
a = recessive allele

p + q = 1
Where p = frequency of A allele
q = frequency of a allele

p2 + 2pq + q2 = 1
Where p2 = frequency of AA genotype
2pq = frequency of Aa genotype
q2 = frequency of aa genotype

Week of 11/3-7

Monday- Continued from last week

Tuesday-Also continued from last week by playing Biology themed trouble.

Wednesday- Continued from Tuesday

Thursday- Today we were supposed to have a Test: Evolution and Taxonomy but it was delayed because we were behind. Instead we had lecture today.

Friday: Today we assessed, described and explained adaptations affecting survival and reproductive success, such as: Structural adaptations in plants and animals (form to function), disease-causing viruses and microorganisms, and co-evolution.

Main ideas today included:

• Feeding adaptations.
• Adaptations to ensure successful reproduction.
• Adaptations to life on land.
• Structure of viruses.
  
• Mutation of viruses and other microorganisms.
  
• Variety of disease causing (pathogenic) agents (viruses, bacteria) including: 
  
• HIV
  
• Influenza
  
• Smallpox
  
• Streptococcus (strep throat)
  

Week of 10/27-31

Monday- Today we learned how to use dichotomous keys to identify and classify organisms.

Tuesday- We discussed similarities and differences between eukaryotic and prokaryotic organisms, and similarities and differences among the eukaryotic kingdoms: Protists, Fungi, Plants, and Animals.

A few notes include:

• Membrane bound organelles - none in prokaryotes.
• Ribosomes in both.
• Contrasts in chromosome structure.
• Contrasts in size.
• Cellular structures.
• Unicellular vs. Multicellular.
• Methods of making/getting food and breaking down food to get energy.
• Reproduction.

Wednesday- Today we analyzed the process by which organisms representative of the following groups accomplish essential life functions including: Unicellular protists, annelid worms, insects, amphibians, mammals, non-vascular plants, gymnosperms and angiosperms. The functions are transport, excretion, respiration, regulation, nutrition, synthesis, reproduction, and growth and development.

The functions are described as:

• Transport- how organisms get what they need to cells; how they move waste from cells to organs of excretion.
• Excretion- how organisms get rid of their waste and balance their fluids (pH, salt concentration, water).
• Regulation- how organisms control body processes - hormones, nervous system.
• Respiration- how organisms get oxygen from the environment get oxygen from the environment and release carbon dioxide back to the environment and how plants exchange gases.
• Nutrition- how organisms break down and absorb foods.
• Synthesis- how organisms build necessary molecules.
• Reproduction- sexual versus asexual, eggs, seeds, spores, placental, types of fertilization.
• Growth and development- metamorphosis, development in egg or in uterus, growth from seed or spore.

Thursday- Today we had a sub and completed our chart using the textbook.

Friday- Today we watched the "March of the Penguins" and analyzed the movie to determine how Penguins accomplish essential life functions including: transport, excretion, respiration, regulation, nutrition, synthesis, reproduction, and growth and development. 

10/20-24/08

Monday- Another repeat day, we turned our labs in today.

Tuesday- Today we included the topic of the origin and history of life.

In today's lesson we talked about:

• Biogenesis in contrast to abiogenesis with emphasis on the experiments used to support both ideas.
• Early atmosphere hypotheses and experiments.
• How the early conditions affected the type of organism that developed (anaerobic and prokaryotic).
• Evolution of eukaryotic and aerobic organisms.
• The importance of the environment in selecting adaptations.

Wednesday- Today we examined the development of the theory of evolution by natural selection including: fossil and biochemical evidence.

We talked about:

• Historical development of the theory of evolution by natural selection.
• Fossils-relative and absolute dating methods
• A discussion of what can be inferred from patterns in the fossil record.
• Biochemical similarities.

Thursday- The only differences today was that we learned about the mechanisms of evolution and the applications (pesticide and antibiotic resistance).

We discussed: 

• How variations provide material for natural selection.
• The role of geographic isolation inspeciation.
• Discuss the evolutionary selection of resistance to antibiotics and pesticides in various species.

Friday- Today we analyzed the classification of organisms according to their evolutionary relationships, and the historical development and changing nature of classification systems.

Notes today were:

• Originally two kingdoms (plants and animals). More kingdoms added as knowledge of the diversity of organisms increased.
• Development of the seven level classification system (KPCOFGS) and binomial nomenclature
• Evolutionary phylogeny, DNA and biochemical analysis, embryology, morphology
• Interpret phylogenetic trees

Week of 10/13-10/17

Monday- Continuation of last Friday

Tuesday- Today we started lab which would model if evolution occurs and if the Hardy Weinberg equilibrium holds true. 

Wednesday- Today we basically collected data through a survey.

Thursday- We finished the lab and started our lab write ups which trust me is a tedious process.

Friday- Today we had a sub and a lot of textbook work.

Week of 10/6-10/10

Monday- We assessed the impacts of genomics on individuals and society by reviewing the human genome project and by looking at the applications of biotechnology.

We discussed:

• The reaons for establishing the human genome project.
• Recognition that the project is useful in determining whether individuals may carry genes for genetic conditions and in developing gene therapy.
• Gel electrophoresis as a technique to separate molecul;es based on size.
• Uses of DNA fingerprinting
• Apllications of transgenic organisms (plants, animals, and bacteria) in agriculture and industry including pharameutial applications such as the production of human insulin.
• Ethical issues and implications of genomics and biotechnology. (Stem cell research and genetically modified organisms)

Tuesday- Same as Monday

Wednesday- Same as Monday

Thursday- Today we had a Biology Benchmark

Friday- Today we examined the development of the theory of evolution by natural selection including: development of the theory and mechanism of evolution.

A few notes were: How variations provide material for natural selection, the role of geographic isolation in speciation, and the importance of the environment in selecting adaptations.

Urine

Urine consists of urea and water. Urea is somewhat like ammonia since it is toxic to cells. This aspect of urea makes urine sterile. Freshwater fish must urinate alot because the water level in their cells is lower then the surrounding environment. Saltwater fish urinate very little because the water level in their cells is higher then the surrounding environment. Organisms waste energy in the form of heat energy. Saltwater fish urinate by allowing water to brush off the urea located on their gills. The loop of Henle in the kidney reabsorbs water and ions from urine. 

How do Hormones work?

Natural selection-Amino acid sequence-Proteins-DNA

Nobody has a full understanding of hormones, people just know that they are another phase of development. By age 6 almost 95% of hormones are already in affect. Before puberty cells go through a growth spurt. Hormones affecting humans have been compared to a tree's development. During puberty humans are very vulnerable, have many mood swings, and use or lose cell connections. Simply hormones are just proteins.

Why is life based on Carbon?

Life is based off of carbon because carbon allows itself to form bonds with other atoms and can bond to other carbon atoms with one, two, or three bonds. It easily bonds up to four times and can form virtually unlimited chains. The simplicity of structures come together to build longer and more complex chains, but many combinations do not work putting a limit on the length of a carbon chain. The working chain has to be able to duplicate or recreate itself. If a chain cannot then it is a dead end and it not fit for survival.

Virus

A virus is a highly characterized parasite, that mutates and evolves. A virus also interacts with a population by keeping it from overproducing. Viruses reproduce by infecting a host cell and using its organelles to create numerous copies of itself.A virus has all to be living but it falls just short of the definition of living organisms.

Origins of Life

Amino acids can be found within meteors and other stellar objects. Amino acids make up proteins which are the building blocks of life and can be altered under extreme conditions to create larger and more complex amino acids. An extreme condition occurred when Meteors hit the Earth, which occurred in Earth's early history. There is an unexplainable question between how microbes were created from amino acids. Microbes got started in extreme conditions and may have had their building blocks from outer space. After the bombardment 3.5 bya microbes started photosynthesizing and allowed green slime to take over the earth. The oxygen as a waste gas created an ozone that allowed complex life forms to take hold. The oxygen level rose from less then 1% to 21% which allowed complex life forms to take hold.

An Introduction to Metabolism

• Enzymes speed up metabolic reactions by lowering energy barriers
• Enzymes are substrate specific
• The activation site is in the enzyme's catalytic center
• A cell's physical and chemical environment affect enzyme activity.
• Organic Compounds= living system, questions about how life takes the step from chemicals to life
• Chemistry of living has to be controlled, this control comes from enzymes
• Nonliving things do not have to be controlled
• Reactions occur fast enough to keep us alive thanks to enzymes

Periodic Table

• Why is life based on carbon
• proton-positive
• Uranium highest stable atom
• 186,000 miles per second electron
• no matter is solid
• first orbit is 2 for oxygen
• atomic theory 2-8 electrons
• Hydrogen one orbit, one electron
• Biological four groups are lipids, carbohydrates, nucleic acids, and proteins
• Not correct type of atoms to live on Mars
• The environment is adapted to us
• The theory of evolution is credited to Charles Darwin
• Lipids=cell membrane
• Sugar is are main energy source

Science

• Philosophy of thought
• Bad science is combustion engine
• State question
• Form Hypothesis
• Test Hypothesis
• Conclusion
• Not measurable=not science
• Will never do good science in biology
• 99.9% is the highest degree in science
• Theory supports fact and vice versa
• Facts change
• Belief isn't science

Genes

1. Book-Human, Name-Genome, consists of AT's and GC's
2. Chapter-Chromosome
3. Sections-Genes and Protein synthesis
4. Paragraphs-mRNA-transcription and gene splicing
5. Sentences-Gene structure, Start-->Functional partion-->Stop
6. Words-Codons-64
7. Letters-base pairs-AT, GC, U/ which are nitrogen bases

Mitosis

The stages of Mitosis are as follows:

• Interphase- The cell grows and replicates its DNA and centrioles.
• Prohase- The chromatin condenses into chromosomes. The centrioles separate, and a spindle begins to form. The nuclear envelope breaks down.
• Metaphase- The chromosomes line up across the center of the cell. Each chromosome is connected to a spindle fiber at its centromere.
• Anaphase- The sister chromatids separate into individual chromosomes and are moved apart. 
  
• Telophase- The chromosomes gather at opposite ends of the cell and lose their distinct shapes. Two new nuclear envelopes will form.
• Cytokinesis- The cytoplasm pinches in half. Each daughter cell has an identical set of duplicate chromosomes.

week of 9/29-10/3

Monday= TEST

Tuesday=Today we analyzed the molecular basis of heredity which includes gene regulation. 

A few bullets include:

• All (with a few exceptions) of an organism's cells have the same DNA but differ based on the expression of genes.
• Differentiation of cells in multicellular organisms
• Cells responding to their environment by producing different types and amounts of protein.
• Advantages (injury repair) and disadvantages (cancer) of the overproduction, underproduction or production of proteins at the incorrect times.

Wednesday-Thursday= We learned to interpret and predict patterns of inheritance which also includes dominant, recessive, and intermediate traits. Also multiple alleles, polygenic traits, sex linked traits, independent assortment, test cross, pedigree, and Punnett squares were discussed in class.

We learned alot of information during the course of these two days. A summary is as follows: 

• We identified and determined genotypes and phenotypes. Phenotypes are the result of both the environment and the genotype.
• We also discussed Mendel's experiments and laws.
• Interpreted karyotypes and looked for gender and chromosomal abnormalities.
• Understanding that dominant traits mask recessive alleles.
• There are a variety of intermediate patterns of inheritance, including codominance and incomplete dominance. Incomplete dominance (partial dominance) results in the blending of traits and Co-dominant alleles result in the expression of both traits. We also learned how to solve and interpret co-dominant crosses involving multiple alleles.
• Autosomal inheritance patterns and characteristics of sickle cell anemia, cystic fibrosis, and Huntington's disease.
• Parentage is possible by determining the parents and offsprings blood type. There are A, B, AB, and O blood types which result from alleles Ia, Ib, and i.
• Recognizing that some traits are controlled by more than one pair of genes, which is identified by the presence of a wide range of phenotypes.
• An understanding of human sex chromosomes and crosses involving sex linked traits. Males are more likely to express a sex linked trait because they only have one X chromosome that is infected and they don't have another X chromosome to mask this allele.
• The process of meiosis leads to independent assortment and ultimately to a greater genetic diversity. Genes being on separate chromosomes is an important result of meiosis.
• Given certain phenotypes suggest an appropriate test cross to determine the genotype of an organism. and identify the genotypes of individuals from a given pedigree.
• Finally we learned about solving and interpreting problems featuring monohybrid crosses, (Parental, F1, F2 generations) and about determining parental genotypes based on offspring ratios. 

Friday= Today we reviewed what we learned last Friday, with the addition of a few things.

We learned about the uses of DNA fingerprinting, applications of transgenic organisms in agriculture and industry including pharmaceutical applications such as the production of human insulin, and that ethical issues and implications of genomics and biotechnology such as stem cell research and genetically modified organisms.

Week of 9/22-26

Monday=We analyzed the molecular basis of reproduction which is called DNA replication. 3.01

DNA unzips through DNA polymerase and two chains are produced. These chains each go through base pairing where certain chemicals combine with the existing chemical to form an exact copy of the original DNA. This is a semi-conservative process as the two strands are built upon with another chemical. A attaches to T and G attaches to C. 

Some important things about DNA are: mutations can change DNA code, the replication of DNA within the cell cycle, that DNA has weak hydrogen bonds which allow it to break apart and form two new strands of DNA, its structure, and that it replicates itself through complementary base pairing.

Tuesday=We reviewed what we learned about asexual and sexual reproduction from Friday.

Wednesday=Continuation of Tuesday's lesson plan of review.

Thursday=We learned about the aspects of protein synthesis which are transcription and translation. 

We learned to understand that the sequence of nucleotides in DNA codes for proteins which are the central key to cell function and life.

Protein Synthesis:

• Transcription produces an RNA copy of DNA, which is further modified into the three types of RNA. 
  
• mRNA traveling to the ribosome (rRNA)
• Translation-tRNA supplies appropriate amino acids
• Amino acids linked by peptide bonds to form polypeptides which are folded into proteins.
• Use of a codon chart to determine the amino acid sequence produced by a particular sequence of bases.

Friday=The human genome project and applications of biotechnology were taught today.

Today we developed an understanding for the reasons for establishing the human genome project, usefulness in determining whether individuals may carry genes for genetic conditions, and in developing gene therapy.

Lastly we watched a movie on cloning, and had a discussion about the role of cloning in our future and the moral issues concerning cloning.

Week of 9-15/19

Monday=Continued from last Thursday and Friday but with the addition of one thing. We learned about Energy use and release in biochemical reactions. ATP is the source of energy for cell activities, and cells store and use energy in ATP and ADP molecules.

Tuesday=Today we investigated and analyzed the following bioenergetic reactions: aerobic respiration, anaerobic respiration, and photosynthesis. We also learned the equations to photosynthesis 6CO2+6H2O(Reactants)-->O2+C6H12O6(Products) and cellular respiration 6O2+C6H12O6-->6CO2+6H2O. We also learned about factors that affect the rate of photosynthesis and of cellular respiration. 

Anaerobic respiration includes lactic acid and alcoholic fermentation. We compared anaerobic and aerobic organisms in class.

Finally we compared and contrasted these processes with their regard to efficiency of ATP formation, the types of organisms using these processes, and the organelles involved. 

Wednesday=Continuation from Tuesday

Thursday=Cricket Lab

Today we tested if males or females respire at different rates. My group concluded that the male cricket consumed more oxygen and produced more carbon dioxide in a 90 second session then the female cricket. This may have been affected by the high levels of testosterone in the male crickets.

Friday=Today we compared and contrasted the characteristics of asexual and sexual reproduction.

• We recognized mitosis as a part of asexual reproduction and meiosis as a part of sexual reproduction.
  
• We noted similarities and differences between mitosis and meiosis including: replication and separation of DNA and cellular material, changes in chromosome number, number of cell divisions, and number of cells produced in a complete cycle.
• We also put together mitosis diagrams and described what happened at each phase during the process.
• Finally we learned about the sources of variation which included: crossing over, random assortment of chromosomes, gene mutations, nondisjunction, and fertilization.

Week of 9/8-12

Monday= Continuation of Friday's review.

Tuesday= Major Exam today.

Wednesday-Friday= Continual review of past concepts.

This week was used to review and test upon previous concepts. 

Week of 9-2/5

Monday=No school

Tuesday= Continuation of Friday

Wednesday= Reviewed the cell concepts we learned last week.

Thursday= Reviewed communication among cells within an organism.

Friday= Reviewed the maintenance of homeostasis, and the movement of materials into and out of cells.

Week of 8:25/29

Monday and Tuesday= These days we continued to learn about enzymes.

Wednesday- We investigated and described the structure and functions of cells, their organelles, and their specializations. 2.02 

• We also learned about the structure and function of: nucleus, plasma membrane, cell wall, mitochrondria, vacolues, chloroplasts, and ribosomes.   
  
• Proficient use and understanding of light microscopic techniques. Total power magnification as well as steps in proper microscope usuage.
• Hierarchy of cell organization: Cells to tissues to organs to organ systems.
• Structure of cells as it relates to thier specific functions.
• We also viewed a variety of cells with particular emphasis on the differences between plant and animal cells. 

Thursday= We learned about communication among cells within an organism.

Chemical signals may be released by one cell to influence the activity of another cell. For example, a nerve cell can send a message to a muscle cell or another nerve cell. Recepotr proteins and hormones were also discussed in class today.

Friday= We investigated and analyzed the cell as a living system including: the maintenance of homeostasis and the movement of materials into and out of cells.

We also learned about factors affecting this such as temperature, PH, blood glucose levels and water balance. Active transport, passive transport, diffusion, osmosis, and the porous nature of the semipermeable plasma membrane were also discussed. Something we learned today was how to predict changes in osmotic pressures as cells are placed in solutions of differing concentrations. 

Sex Chromosomes

The Sex Chromosomes are X and Y. XX is a female and XY is a male. These chromosomes come from the gametes which are an egg and a sperm cell. A sperm cell is either X or Y and an egg is a X. The SRY triggers testis growth in the 8th week of prenatal development and is located on the Y chromosome. All embryos are female until the SRY kicks in. There are many exceptions and dieases linked to these sex chromosomes.

Pictures

Red Blood cells

A gene is a segment of DNA that is involved in producing a polypeptide chain; it can include regions preceding and following the coding DNA as well as introns between the exons; it is considered a unit of heredity.

Its function is to carry out protein synthesis. Protein synthesis is when amino acids are linked together in peptide chains which are dictated by the sequence of nucleotides  in DNA; this governing sequence is conveyed to the synthesizing apparatus in the ribosomes by mRNA, which is formed by base-pairing on the DNA template.

Here is a lengthy web definition in more detail: During the process of transcription, the information stored in a gene’s DNA is transferred to a similar molecule called RNA (ribonucleic acid) in the cell nucleus.

Translation, the second step in getting from a gene to a protein, takes place in the cytoplasm. The mRNA interacts with a specialized complex called a ribosome, which “reads” the sequence of mRNA bases. Each sequence of three bases, called a codon, usually codes for one particular amino acid. (Amino acids are the building blocks of proteins.) A type of RNA called transfer RNA (tRNA) assembles the protein, one amino acid at a time. Protein assembly continues until the ribosome encounters a “stop” codon (a sequence of three bases that does not code for an amino acid).

It is controlled by separate transcriptional controls on each gene. A transciptional control controls a gene expression by controlling the number of RNA transcripts of a region of DNA. This is a major regulatory mechanism for differential control of protein synthesis in both pro and eukaryotic cells. 

Red blood cells originally have a nucleus when they are formed in the bone marrow but their nucleus disintegrates so that the cell can hold more oxygen and because the nucleus consumes the most oxygen from all the cell organelles. A web definition of red blood cells: a mature blood cell that contains hemoglobin to carry oxygen to the bodily tissues; a biconcave disc that has no nucleus.

Week of 8-18/22

Monday- We continued learning about the organic molecules: Carbohydrates, Proteins, Lipids, and Nucleic acids. We also started exploring theories on the Origin of life.

Tuesday- We examined the role and importance of organic molecules to organisms. A lab was conducted today where each group tested for starch with iodine, tested for lipids with brown paper, tested for monosaccharides with Benedict's Solution, and tested for protein using Biuret's.

During this experiment we learned to distinguish among mono, and polysaccharides. We placed special emphasis on the functions and subunits of each organic molecule. An example of this would be-an enzyme is a protein composed of long chains of amino acids that are folded into particular shapes and whose shape determines the specific reaction the enzyme will catalyze.

Wednesday- Today we investigated and described the structure and function of enzymes and explain their importance in biological systems. 2.04

Three important bullets about enzymes are:

1. Enzymes are proteins that speed up chemical reactions (catalyst).



2. Enzymes are reusable and specific.



3. Enzymes are affected by such factors as pH, and temperature.
   
   

This information helped us set up an experiment where we measured how fast the enzyme catalase decomposes Hydrogen Peroxide. Chicken Liver and Potato slices where used. The chicken liver produced more pressure and oxygen then the potato after the experiment was run.

Thursday- Continued from Wednesday.

Friday- Test:Goal#1{The Nature of Science objectives 2.01 2.04}

Week of 8/11-15

Science- Way of life and thinking that involves examining the universe and everything within it or that is involved with it.

Monday- Today we learned about the Scientific Method and how to set up an experiment. 1.01

Tuesday- Today we learned about designing and conducting scientific investigations to answer biological questions. 1.02

The steps are as follows:

• Create testable hypotheses.
• Identify variables.
• Use a control of comparison group when appropriate.
• Select and use appropriate measurement tools.
• Collect and record data.
• Organize data into charts and graphs.
• Analyze and interpret data.
• Communicate findings.

We also learned about formulating and revising scientific explanations and models of biological phenomena using logic and evidence. This was used to Explain observations, make inferences and predictions, and to explain the relationship between evidence and explanation. 1.03

How to apply safety procedures in the laboratory and in field studies to recognize and avoid potential hazards, and to safely manipulate materials and equipment needed for scientific investigations. 1.04

Finally we learned how to analyze reports of scientific investigations from an informed, scientifically literate viewpoint which includes the ability to consider whether a appropriate sample is given, the experimental controls are adequate, the findings can be replicated, and that alternative interpretations of data are given.

Wednesday- Continued from Tuesday.

Thursday- Continued from Tuesday.

Friday- Today we learned about comparing and contrasting the structure and functions of the following organic molecules: Carbohydrates, Proteins, Lipids, and Nucleic acids. 2.01

Basically today we defined what life is and its characteristics.