11.4 Warm Up

1.      What are the steps in oogenesisi?

         Primordial germ cell divide by mitosis to produce two Oogonia. These cells are all Diploid.

·         Each Oogonia also undergoes mitosis to produce two diploid Primary Oocytes

·         Each Oocyte starts to undergo meiosis I replicating their DNA, but stops in at prophase I

·         There are approx 400,000 primary follicles present in the ovary prior to puberty.

·         A Primary follicles (prophase I) may develop to secondary follicles (metaphase II) under the influence of FSH.

·         Note that the first polar body ( haploid set chromosomes) does not progress beyond metaphase II.

·         The Oocyte does not progress to the end of meiosis unless fertilisation takes place.

1.      What are the steps in spermatogenesis?

Spermatogonium (2n) are found at or near the basement membrane. Cell division by mitosis to produce spermatogonia. The spermatogonium grow to form Primary Spermatocytes which have completed S-phase. The Primary spermatocytes separate the homologous pairs of chromosomes in meiosis I to form the haploid Secondary Spermatocytes. The spermatids are formed from the separation of the sister chromatids in meiosis II. The spermatids are found in association with the sertoli cells which nourish the spermatids as they differentiate into spermatozoa. The rate of spermatozoa is high and continuous throughout the life on the sexually mature male. The average number of spermatozoa in ejaculated semen is 32 x 10⁶ ml^-1

^{The difference between the two?}

Warm Up, kidneys and immunization

1. A blod clot contains a network of protein. What is the protein?

Clotting Factors

2. Outline how the liquid that flows through the proximal convoluted tubule (PCT) is produced.

Unfiltered blood goes through the afferent arteriole into the glomerulus
This structure, the glomerulus, is held by the Bowan's Capsule.
 It goes from a high pressure to a low pressure gradient in the glomerulus. 
Ultrafiltration occurs here, and then filtered blood travels through the efferent arteriole to the PCT.

3. State the name of the substances reabsorbed by the PCT.

Water, all glucose, all amino acids and mineral ions

4. Discuss the benefits and dangers of immunization against bacterial and viral infections.

Benefits	Dangers
Complete extermination of disease forever Example: Smallpox is now unseen	Excessive vaccination may reduce the effectiveness of the immune system to respond to new infections.
Reduction in death rates from disease Example: Death from Measles is uncommon	Vaccine immunity is less effective than natural immunity Example: Measles
Reduced long term disabilities Examples: Polio paralyzed, blindness in rubella babies	Side effects Example: possible autism from MMR

Antibodies!!!

1      Explain antibody production 

1.       Plasma cells synthesize (make) antibodies that have a complementary structure to its antigens’ epitope (part of an antigen that is recognized by the immune system-antibodies)

2.       Antibody binds to the antigen and then binds them to the other antigens- called agglutination

3.       This concentrates the antigen and makes it easier to engulf (Eat) by phagocytic (a type of cell capable of engulfing things) lymphocytes.

-          Binding of antibody may inactivate the antigen directly

-          The immune system has memory of the antigen in the Bm cell 

          Describe the production of monoclonal antibodies and their use in diagnosis and treatment

1. A specific B cell is selected that can produce the required antibody

2. A tumor cell (capable of endless cell division) is selected

3. The two cells are joined together (HYBRIDIZED)

4. The resulting HYBRIDOMA is capable of synthesizing large quantities of antibodies

Diagnosis of HIV infections using monoclonal antibodies

The test of HIV infection is based on detecting the presence of HIV antibodies in lblood serum

Test results in a qualitative color change

1. The HIV antigen is attached to a plate

2. The patient’s serum is passed over the plate were any HIV antibodies present will attach to the antigen on the plate

3. A second antibody (specific to the HIV antibody) is passed over the plate, a will attach to the concentrated HIV antibody. This second antibody ha an enzyme attached to it.

4. Chromagen dye is passed over the complex of concentrated HIV antibody

5. The enzyme will turn the chromagen to a more intense color, the more the color, the greater the HIV antibody level.

Treatment of Rabies using Monoclonal Antibodies

-  Rabies infection can be treated by injection of antibodies

-  The antibodies are made by monoclonal antibody technology

-   Other: cancer treatment, transplant tissue typing, purification of industrial products

Blood Warm Up

Describe the steps of blood clotting!!!

Clotting- the way the body prevents blood loss when vessels are broken

The steps to clotting as are follows!

1.      The damaged cells release a protein called CLOTTING FACTORS!

These little guys are released into the plasma and head over to the wound site.

2.      The clotting factors activate the enzyme THROMBIN,

 which then turns the soluble plasma protein FIBRINOGEN into its insoluble fibrous form FIBRIN!

3.      Fibrin then comes and saves the day by binding together platelets and blood cells.

 This creates a plug called a clot

. 

Outline the immune response to an antigen

 The antigen’s epitope is detected by a large white blood cell called a macrophage

            The macrophage eats the antigen and digests it .

            It moved to the lymph nodes

The lymph nodes contain a wide variety of B lymphocytes

Corresponding B or T Lymphnodes are selected

Lymphnodes rapidly divide to form a clone of Plasma cells and B memory cells

 

Discuss active vs. passive immunity

Active Immunity- immunity that is a result of the production of antibodies by the organism itself. This is done after the body’s mechanism have been activated by an antigen

Passive immunity- immunity due to the acquired antibodies from another organism in which active immunity has been stimulated

 

 

 

Genetics! Defenitions and practice question

Homozygous- Having two identical alleles that code for the same trait.

Phenotype- The physical characteristic expressed by a gene.

Carrier- A heterozygous individual who has an unexpressed recessive gene for a trait 

Can a mom with A blood and a dad with B blood have children with O blood?

Yes

Can a Mom with hemophilia and a dad that is normal have children with hemophilia?

Yes, if it is a boy.

Warm Up Statistical Data

1. What is the importance do standard deviation with regards to the mean ?

The standard deviation is the average amount by which the data points differ from the mean. Basically how far from the mean the data points are.

2. What do error bars indicate?

error bars are a graphical representation of the variability of data

3. What percentage of values fall within 1 standard deviation of the mean? And 2?

68% of the values fall within one standard deviation of the mean
95% of the values fall within two standard deviation of the mean

Warm up

List the steps for germination of starchy seed.

The processes of germination begins with the absorption water. This causes the production of gibberellin acid, GA for short. The GA then causes the synthesis of amylases which is used to break down starch and make it into maltose. This maltose is then transported to the embryo and used for two different purposes. It could either be made into glucose (energy for the embryo) or polymerized to cellulose (for cell wall formation). The absorption of water will also form enzymes, triglycerides and phospholipids out of the stored proteins and lipids. Germination uses the food stored in cotyledons as an energy source until the developing shoot reaches the light and can begin to make its own food through photosynthesis.

 

Explain how flowering is controlled in long day and short day plants, including the role of phytochrome

Phytochrome  is affected by light and controls flowering.  Phytochrome exists in two forms Pf and Pfr. The P_fr form is the active form of phytochrome, while the P_r form is the inactive form of phytochrome. Sunlight is composed of more red light then far red, so the P_fr form is mostly active during the day, with the P_r form is mostly active at night.
 In long day plants, the active P_fr form is a promoter of flowering and so flowering is induced when the night period is less than a critical length and P_fr levels are high. In short day plants, the active P_fr form is an inhibitor of flowering and so flowering is induced when the night period is greater than a critical length and P_fr levels are low.

Warm Up: Plant Science Part Two!!!

1. Of what value are tubers, a type of stem modification, to the survival of a plant species?

Tubers are a modified plant structure that are enlarged to store nutrients. They are used by plants to survive the winter or dry months, to provide energy and nutrients for regrowth during the next growing season.

2. When moving a plant from one place to another, why is it important to leave original soil around the roots?

It is important to leave original soil around the roots of a plant when moving its location because the original soil will allow the plant to have a nice transition to its new environment. It lets it slowly adapt and become situated in the new location. If it were to be moved without any original soil, the change may be too drastic or fast for the plant to be able to process it and adapt. This might lead to a very sad death. 

3. What is the usual cause when a plant wilts?

The cause for a plant wilting is usually a lack of water in the plant's cells, which is means it has a lower turgidity. This reduces its ability to remain rigid or erect. The poor guy sadly wilts from thirst!

4. Explain when a seed would be a sink and when it would be a source

Source: produces and stores carbohydrates
Sink: consumes those carbohydrates
 The movement of carbohydrates occurs from where carbohydrates are made or have been stored, called a source, to where they will be stored or used, called a sink.

5. Why is it necessary that veins are relatively close together in the leaves?

Distance between veins shows how well the veins are supplying resources to the leaf. Plants with denser vein networks -- veins that are closer together -- are able to withstand higher levels of water loss and absorb more carbon.