What it is long term depression in neuroscience?

Explain clonal selection and how it works to protect you against many different infectious agents.

Which yields more ATP, fats or carbs? Using a flow chart, indicate how many ATP molecules are generated from the complete oxidation of 2 glucose molecules. Contrast with the complete oxidation of a 12-carbon fatty acid. In your discussion indicate how many NADH and FADH2 and ATP are produced and in what pathway. Your final answer should be expressed as the #ATP /2 glucose and #ATP/12-C fatty acid. (5 marks)

10. Fill in the blank: In vitro irradiation of macromolecules causes _____ damage to macromolecules. A) Repairable
    2. Reversible
    3. Irreversible
    4. Both A and B

10. Localized doses of 7 Gy to the skin can cause:
    1. Death
    2. Permanent hair loss
    3. Gastrointestinal syndrome
    4. All of the above

If a cell gained a gene that allowed it to produce more or different compatible solutes, what environments could it live in better?

CHOOSE THE CORRECT ANSWER AND EXPLAIN FOR EACH OPTION WHY YOU DID NOT CHOOSE THAT OPTION.

Arrange the following events in steroid function in chronological order. Number each statement

from 1-5.

_____Level of estradiol increases

_____Decrease in the thickening of uterine lining

_____Ovulation triggered by luteinizing hormone

_____If no ovum is fertilized, progesterone and estradiol production stops

_____Bleeding due to sloughed off uterine lining

a. 3, 2, 4, 1, 5

b. 3, 1, 4, 2, 5

c. 1, 4, 3, 2, 5

d. 1, 4, 2, 3, 5

Arrange the following events in lipid transport in chronological order. Number each statement from 1-5.

____ Cell use the cholesterol as part of the membrane

____ apoB-100 binds to LDL-receptor in coated pits

____ VLDL contains triglycerides and cholesteryl esters

____ Endocytosis of LDL into the cell

____Removal of all VLDL molecules except for the cholesteryl core

a. 5, 3, 1, 4, 2

b. 5, 4, 3, 2, 1

c. 3, 1, 4, 5, 2      

d. 3, 5, 2, 1, 4

Which of the following pairs would form hydrogen bonds?

A. Gly-Ala    B. Ser-Asp   C.Val-Ile      D. Phe-Thr

Which peptide sequence has an aromatic residue?

A. L-C-D-V-G-T

B. I-K-R-Y-N-E

C. M-P-A-Q-S-D

D. T-C-S-L-Q-G

Food chains are typically quite short, with only 4-5 links. Which of the following explains why? Only one species of herbivore feeds on each producer species. Predator species are usually less diverse and less abundant than prey species. Most of the energy at each trophic level is lost rather than passing on to the next level. Extinction of species at one level causes extinctions at higher levels. 1 points

QUESTION 47 Which of the following is a characteristic of all chordates at some point during their life cycle? vertebrae four limbs four-chambered heart jaws post-anal tail 1 points

QUESTION 48 Which of these is a major trend in land plant evolution? the trend toward larger gametophytes the trend toward smaller size the trend toward a gametophyte-dominated life cycle the trend toward a sporophyte-dominated life cycle 1 points

QUESTION 49 The phytochrome system is involved in which of the following plant responses? none of the responses involve the phytochrome system photoperiodism all of these responses involve the phytochrome system negative phototropism positive phtotropism 1 points

QUESTION 50 Approximately how many kilocalories (kcal) of a secondary consumer's energy requirements can be supported by a community containing 100 kcal of producers? 0.1 kcal 10 kcal 1 kcal 0.01 kcal 1 points

QUESTION 51 Vertebrates and urochordates share which of the following traits? a high degree of cephalization (i.e., a well-developed head) a notochord and a dorsal, hollow nerve cord vertebral column jaws adapted for feeding

what are the effector mechanisms of CD4 and CD8 T cells?

Identify two factors that could possibly cause a population to decline to extinction. How might these factors be influenced by population size? Why are small populations more susceptible to extinction from demographic stochasticity than are larger populations?

Meiosis is a process that can generate nearly infinite variation from a single source of genes, even before the additional diversity created by fertilization. There are two main processes that occur during meiosis to generate diversity. Describe each of these processes, referencing where in the meiotic cycle they occur and how they contribute to genetic diversity in the gametes. Format your answer into parts (i) and (ii) for the two processes.

In a 50µl reaction containing 0.25 pmol of a Michaelis enzyme with Km = 4.0 x 10-7 M and substrate concentration of 2 x 10-7 M, product was formed at an initial velocity of 5.0 x 10-5 Mmin-1 .

a. If the enzyme concentration is doubled to 0.5 pmol in the reaction, how much will the velocity increase? Show mathematically

What is the characteristics of anthrax spores that make disinfection more difficult?

Some scientists are concerned that genetic engineering allows humans to tamper with evolution. Discuss some of the advantages and disadvantages of recombinant DNA technology.

QUESTION 57 Imagine a community with a biodiversity of 25 species. One species is hunted to extinction by humans, after which the community is protected from any human intervention. However, a year later, you find that biodiversity is down to 5 species. What does this tell you about the species that went extinct due to hunting? It must have been a producer. It was a virulent pathogen. It was a weak competitor. It may have been a keystone species. It must have been a predator. 1 points

QUESTION 58 In plants, the _______________ are female structures. archegonia and ovule antheridia pollen grains stamens stamen and pollen antheridia and archegonia 1 points QUESTION 59 Which of the following was not one of the observations or inferences that Darwin made relating to his theory of evolution by natural selection? Traits are inherited by offspring if the traits are heritable. Individuals with advantageous traits are more likely to survive and reproduce. All species are capable of reproducing more offspring than the environment can support. Traits that an individual develops during their lifetime are inherited by their offspring. The traits within a population vary. 1 points

QUESTION 60 Which plant tissues are diploid? microspores megaspores gametophyte zygote

Note several ways that cytokines regulate the immune response, with particular emphasis on mechanisms to slow down or limit the immune response. In your answer, discuss why you think these control features are important and describe a potential therapeutic application of one of the control mechanisms, including possible applications of this potential therapeutic treatment.