Chapter 19

Describe the progressive nature of determination.

• Cell determination is the molecular decision where a cell become destined for a particular developmental pathwway.

• Before they become determined,

How do cells become committed to developmental pathways?

There are 2 ways;

1. by the differential inheritance of cytoplasmic determinants (having particular protiens in the cells that effect gene expression), which are maternally produced and deposited into the egg during oogenesis

2. by cell to cell interactions (cells in the zigote, communicate with each other).

What is the difference between the different types of stem cells?

totipotent - a cell that can give rise to any tissue in an organism

pluripotent - Cells that can give rise to all of the cells in the organisms body.

multipotent - a stem cell that can give rise to a limited number of cell types,

What is the difference between reproductive and therapeutic cloning?

reproductive cloning - Cloning an individual

• you need a cell from the animal you want to clone and use its nueous

therepeutic cloning - replicate the tissue in order to treat diseases.

What is the importance of Hox genes in evolution?

Hox genes build the body, are seen in all parts of the body.

• their purpose is to build the body,

• hox genes are more basic, and are body building genes.

• mutations can put different parts, where they aren’t supose to be.

How does cell death contribute to morphogensis?

apoptosis - where cells are programed to die shrivel and shrink.

Chapter 26

What is the main structure of viruses and their genomes?

• All viruses have the same basic structure: a genome of RNA or DNA, surrounded by a protein shell/coat.

How are viruses obligate cellular parasites?

They only effect specific hoast, and specific types of cells.

Distinguish between lytic and lysogenic cycles in bacteriophages.

lytic cycles - The ciral DNA directs the production of new viral particles by the host cell until the virus kills the cell by causing it to rupture.

lysogenic cycle - the bacteriophage DNA is integrated into the host chromosome, where the prophage is replicated along with the host DNA as the bacterium divides, and may persists as a prophage or enter the lytic cycle and kill the cell.

How can viruses contribute DNA to their host?

When the virus attach to the bacteria, and causes it to attach to the hoast, (us). The virus, identifies bacterial cells, that have similar DNA, and reproduce inside of them.

How does antigenic drift and antigenic shift relate to seasonal flue outbreaks and pandemics?

Antigenic drift - refers to small changes in the HA and NA proteins such that previous vaccine-induced immunity is no longer protective.

• due to general mutations from one virus to another, which makes it easier to eviad immune cells.

• This is why we have to develop new vaccines for the flu virus.

Antigenic shift - occurs when an individual is infected with more than one virus, and the viral genomes are reassorted during infection.

• Where animals, get effected by multiple virus, making a new strain of virus, still the flu, but it is the way that pandemics can occur, since there is a bigger change.

What are chromic and latent viral infections? How are they different?

Latent viral infections - have an intial acute phase of infection followed by period of no or very low viral load, and have intermittent espidodes of viral replication.

• basically they stay dorment in the body for long peroids of time, like HIV.

Chromic viral infections -

How does prion replication and transmission violate the traditional notions of heredity?

Mad cow disease, diseases of the brain, where the brain tissue is destroyed.

• The prion was found to be the potein that infected these areas.

• was caused by proteins that were not folded correctly, and can cause other proteins to be misshappen too.

Chapter 49

What is the importance of osmotic balance?

• Osmotic balance is important to be able to keep our cells stable with enough water inside and outside our cells.

hypotonic - solutes are high conc. inside the cell. expands

hypertonic - solutes are high conc. outside of the cell. shrinks

tonicity - solution is a measure of its ability to change the volume based on the solute conc.

osmolarity -

isotonic - conc. of salts is the same on this inside of the cell and the outside of the cell.

Classify organisms based on their osmotic regulation.

osmoconformers - Conform to their environments, and match their environments (all marines)

osmoregulators - maintain a constant water level inside your body.

How do invertebrate osmoregulatory organs work?

Insects:

malpighian tubeles - help the insect balence the salt,

Vertebrates:

kindey/nephron

What is the role of the loop of Henle in the evolution of vertebrate kidneys?

Helps produce urin, ensure that as the urin move through it, it become more and more concentrated. to we retain as much water as possible.

What are the actions of filtration, reabsorption and secretion?

1. filtration - fluid in the blood is filtered into the tubule system, leaving cells and large proteins in the blood, and a filtrate composed of water and all the blood solutes.

2. Reabsorption - the selective movement of important solutes from the fitrate in the tubule system to the extracellular fluid, returing to the blood stream by peritubular capillaries.

3. Secretion - The movement of substances from the blood into the extracellular fluid, then into the filtrate in the tubule system.

What are the primary components of the kidney?

The nephron.

begins in the ball of capillaries, where fluid moves through the proximal convoluted tutbule, where thing continue to be added or removed from the tube.

How is the nephron structured?

Is made up of the bowmans capsule, promimal tubule, loop of henle, the distal tubule, and the collecting duct.

How does the actions of ADH, aldosterone, and ANP work?

ADH - The antidiuretic hormone, this stops or slows the process of peeing, reabsorbing water into the body.

Aldosterone - stimulates the distal covoluted tubules and collecting ducts to reabsorb NA+ decreasing the excretion of NA+ in the urine.

• pulls Na+ out of the tube, and pulls water out.

• usually used when there is low blood pressure.

ANP - helps cause a reduction in expanded extracellular fluid, volume by increasing renal sodium excretion.

• acts as a diuretic by stopping Na+ from being reabsorded in the kidney

• Helps regulate vascular remodleing and energy metabolism.

Chapter 50

What is the difference between innate and adaptive immunity?

Innate immunity - the part of your system that operates the same way for any infection, fever, cellular response

adaptive - the part of the immune system that adapts or changes based on your symtoms from the viral infection. Very specific.

What are the characteristics of adaptive immunity?

• learns to recongize specific things (molecules on the surface of cells, (AKA antigens) that serve as identifying markers.

• epitopes

How do lymphocytes acquire receptors?

Lymphocytes, DNA rearrangements of the immunoglobulin genes, changes to make the receptor out of the proteins from the genes.

What is MHC (major histocompatibility compex)?

proteins are like display angigens, for they can help ramp up the defense.

What is the difference between humoral and cellular forms of immunity?

himoral - antibody production, targeting the cell. corrinated by helper T cells.

Cellular

What are the functions of a cytotoxic T cell?

a type of T-cell Specifically recognizes and kills “altered-self” cells: virally infect or tumor cells.

• They recognize a specific type of MHC protein, and respond to these cells.

What is the role of the helper T cells?

Specifically recognizes foreign peptides on antigen-presenting cells, inducing the release of cytokines that activate B cells or macrophages.

• The are the main organization of the immune system

What are the functions of a B cell?

Binds specific soluble antigens with its membrane-bound antibody; serves as an antigen-presenting cell to Th cells; on activation differentiates into plasma and memory B cells.

How does antibody diversity is made?

We are able to make many antibodies, because of how our DNA can be changed depending on the antigen.

• any individual T-cells can only make 1 type of antibody, but there are millions of these cells. not every cell will be active only the ones that can make that antibody that we need.

What are autoimmune diseases?

Where the body attacks itself, and isn’t working they way it is supose to be.

Explain the cellular basis of the allergic reaction.

allergies are an over-response to something that is not a threat. This can happen because your cells believe that this thing is dangerous so they activate the antibodies for it inorder to get rid of the allergan.

How do pathogens change antigenuc specificity?

This is an evolutionary biproduct of natural selection inorder to survive, so they change their antigens.

antigeinic drift - subtle changes in the antigens to survive. (seen in chapter 26)

Chapter 51

What are the different types of Hermaphroditism?

sequential hermaphrodtism - individuals can changetheir sex, a process through out their life

protogyny - female change to male

protandry - first male change to female

What are the factors that influence sex determination?

Some animals like retiles are determined by temp. (the environment)

What is the differenced between viviparity, oviparity and ovoviviparity?

(all of these happen internally)

• oviparity - laying eggs

• ovovivparity - eggs develop in the mother, but then give birth to live kids.

• viviparity - placenta, in the person and

What are the advantages of internal fertilization?

External fertilization - Gametes are fertilized outside the body, usually seeing under water

Internal - Gametes are fertilized inside the body, and allows for satey.

What are the sequence of events in spermatogenesis?

• testies are bundles of tiny tubules, and is where meiosis occurs.

How do hormones regulate male reproductive function?

follicle-stimulating hormone - stimulates spermatogenesis

luteinizing hormone - stimulates testosterone by leydig cells.

What are the sequence of events in production of an oocyte?

They form one large daughter cell, and in meiosis the cytoplasm divides unequally inorder for the egg to have all the nurtients for the future baby.

How does ovulation and the female reproductive cycle work?

LH causes the fully developed Graafian follicle to burst in this process, releasing its egg or oocyte.

How do hormones regulate female reproductive function?

HCG - human chorionic gonadotropin - keeps the levels of estadoil and progesteron high, which prevents menstruation, which would terminate the pregnacy, once the eggs is released and fertizilized.

What keep the lining intact is the fertilized egg, which makes sure the hormones intact.

Chapter 52

What are the events/steps involved in fertilization?

Egg activation: just the nucleus of the sperm goes into the egg

What does cleavage mean?

After fertizliation when the zygote is being split into 2. When this happens, the zygote is not getting big, it’s just becoming more and more cells.

What does blastula mean?

a hollow disc, the ball of cells.

How can you differentiate between different cleavage patterns?

holoblastic - the whole zygote divides

meroblastic - only a little portion of the zygote cleavegs, and is seen in yoke rich eggs.

What is the outcomes of gastrulation?

begins with the ball of cells, wher they communicate with each other, and end up forming germ layers, which produces this gastrula stage, which tern into 3 germ layers, endoderm, ectoderm and mesoderm

ectoderm - epidermis of skin, nervous system, sense organs

mesoderm - skeleton, muscles, blood vessel, heart, blood, gonads, kidneys, dermis of skin.

endoderm - lining of digestive and respiratory tracts, liver, pancreas, thymus, thyroid.

What are the extraembryonic membranes called in amniotes?

refers to when they reproduce their offspring is different from fishes and amphibians, have special membranes:

amnion

yolk sac

allantois

chorion - helps with gas exchange,

What is neurulation?

forms the neuro-system and if the neural groove is made. If this isn’t complete it can cause problems in the baby.

What is somitogensis?

The process by which somites form. Somites are bilaterally paired blocks of paraxial mesoderm that form along the anterior-posterior axis of the developing embryo

Describe the hormonal control of the birth process?

Protaglandins begin the uterine contractions, but then sensory feedback from the uterus stimulates the release of the oxytocin from the mother’s posterior-pituitary gland. This postitive feedback mechanism accelerates during labor.

oxytocin makes this process even faster.

Describe the progressive nature of determination.
2. Illustrate with examples how cells become committed to developmental pathways.
3. Differentiate between the different types of stem cellsDescribe the progressive nature of determination.
2. Illustrate with examples how cells become committed to developmental pathways.
3. Differentiate between the different types of stem cellsDescribe the progressive nature of determination.
2. Illustrate with examples how cells become committed to developmental pathways.
3. Differentiate between the different types of stem cellsDescribe the progressive nature of determination.
2. Illustrate with examples how cells become committed to developmental pathways.
3. Differentiate between the different types of stem cells

Describe the progressive nature of determination.
2. Illustrate with examples how cells become committed to developmental pathways.
3. Differentiate between the different types of stem cells.

Describe the progressive nature of determination.
2. Illustrate with examples how cells become committed to developmental pathways.
3. Differentiate between the different types of stem cells.