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Biology: systems Flashcards

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1
Q

What can cause speciation?

A
  • Inbreeding
  • Bottleneck (drastic even wipes out most alleles in gene pool, leaving only a few that are not represenatative of population before)
  • Specialization
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2
Q

Describe Hardy Weinberg equilibrium, and its 5 points.

A

HW equilibrium = NO evolution occurs

  1. mutational equilibrium (forward mutation = backward mutations)
  2. Large population (avoid genetic drift)
  3. random mating
  4. no immigration/emmigration
  5. no selection of fittest organism
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3
Q

Differentiate of viruses get into bacteria vs. eukaryotes>

A
  • bacteria = injects its nucleic acids through a tail after digesting hole in membrane
  • eukaryotes = viruses engulfed by host cell via endocytosis
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4
Q

Differentiate a lytic and lysogenic infection

A
  • Lytic = take hold of host cell and use their RNA (or transcribed from viral DNA) to create new viruses until they burst or release one by one
  • Lysogenic = viral DNA incorporated into host genome, therefore can stay dormant until activated (then go into lytic)
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5
Q

What are viral envelopes and how are they beneficial?

A

envelopes created by host ell membrane that the virus has pinched off and used
-beneficial because protects virus from immune response

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6
Q

Which viral RNA needs an RNA-dependent RNA polymerase?

A

The -RNA, as it creates a complimentary strand that does not code for any proteins, then it undergoes replication by the polymerase to create a +RNA

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7
Q

What is a retrovirus?

A

a virus that uses a reverse transcriptase to transcribe RNA into dsDNA

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8
Q

What is the difference between gram (+) and gram (-) bacteria?

A 
(+) = thick cell wall, so doesn't let stain out - stained PURPLE
(-) = thin cell wall, allows stain to be washed - stained PINK, also has another membrane on top of cell wall that protects from antibiotic
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9
Q

What are the 3 different types of genetic recombination?

A
  1. Conjugation: transfer of plasmids (F and R plasmids)
  2. Transformation: DNA from external into bacterial genome
  3. Transduction: transfer genetic material from a virus using a vector
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10
Q

The nucleolus is where…?

A

Where ribosomal DNA is transcribed

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11
Q

What are lysosomes filled with?

A

acid hydrolyses, with a pH of 5

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12
Q

What are the functions of smooth endoplasmic reticulum?

A

Lipid metabolism, storage and detoxification

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13
Q

What are the functions of peroxisomes?

A

Lipid and protein storage. They also produce and breakdown hydrogen peroxide.

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14
Q

Describe the 3 parts of the cytoskeleton.

A
  1. Microtubules - for transport and support shape of the cell. Make from tubulin.
  2. Microfilaments - Contraction and cleavage. Made from actin.
  3. Intermediate filaments - maintain cell shape
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15
Q

What are the important checkpoints in the cell cycle?

A

G1 checkpoint: checks ratio of DNA:cytoplasm

G2 checkpoint: checks for mitosis promoting factor

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16
Q

Describe the cell cycle and its 4 points.

A

G1: cell growth after dividing
G0: non-growing state (neurons)
S: DNA replication
G2: prepare to divide

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17
Q

What are the differences between the 3 different connections between cells? And an example.

A
  • Tight junctions: water tight seal. Ex. epithelial in bladder, kidney and intestines
  • Desmosomes: joined via the cytoskeleton. Ex. stressed tissues.
  • Gap junctions: tunnels connecting cells. Ex. cardiac and smooth muscle
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18
Q

What photoreceptors are for colour? for black and white?

A

colour = CONES!

black and white = RODS!

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19
Q

When the ciliary muscles in the eye CONTRACT what happens?

A

Lens becomes more sphere and the focal point is closer the the lens

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20
Q

When the ciliary muscles in the eye RELAX what happens?

A

Lens becomes flattened and increases the focal distance

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21
Q

How is the resting potential of a neutron created?

A

Through the diffusion of K+

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22
Q

What is the difference between parallel and convergent evolution?

A

Convergent evolution: when species of different ancestry develop the analogous traits due to similar enviro’s/niches
Parallel evolution: when 2 species evolve independently of each other but remain the same level of similarity. This is NOT due to similar enviros, and it it usually 2 unrelated species.

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23
Q

Where are peptide hormones formed? What are they made out of?

A

In the rough endoplasmic reticulum. They are mostly amino acids, but can contain carbohydrates

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24
Q

What are all the steroid hormones?

A

Cortisol, aldosterone and the androgens

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25
Where do steroid hormones bind?
In the cytosol, because can diffuse through the lipid membrane
26
What are the tyrosine derivative hormones?
T3 and T4, epinephrine and norepinephrine
27
Where are the steroid hormones synthesizeD?
In the smooth endoplasmic reticulum and the mitochondria
28
Where are the tyrosine derivative hormones synthesized?
In the cytosol or the rough endoplasmic reticulum
29
What is the job of antidiuretic hormone (vasopressin) and where is it released from?
- Fluid is reabsorbed, and blood pressure is increased | - released from the post. pituitary
30
Where is oxytocin released from?
The post. pituitary
31
Parathyroid hormone works to______ Ca2+ by _________ the osteoclasts.
- Increase blood Ca2+ | - proliferating osteoclasts (and excretion of phosphate and reabsorbing Ca2+ at kidney level)
32
Calcitonin hormone works to______ Ca2+ by _________ the oteoclasts
- Decrease blood Ca2+ | - inhibiting osteoclast activity
33
What is aldosterones job in the body?
Causes Na+ and Cl- reabsorption and K+ excretion which works to increase blood pressure
34
In male reproduction the Sertoli cells are stimulated by -_________ and their job is to...?
- follicle stimulating hormone | - surrond and nurture the sperm
35
In male reproduction the leading cells are stimulated by __________ and cause production of....?
- luetinizing hormone | - testosterone
36
In female reproduction the granulose cells are stimulated by______ to do what?
- follicle stimulating hormone | - to create the primary follicle
37
In female reproduction the theca cells are stimulated by _______ to produce...?
- luetinizing hormone | - estradiol
38
What is released by the placenta to regulate the estrogen and progesterone levels when pregnant? What type of hormone is it?
-human chorionic gonadotropin (HCG) and it is a peptide hormone.
39
Differentiate the 3 germ layers and what they create (ecto-, meso-, and endoderm)
Ecto- skin, NS, sense organs Meso- skeleton, muscles, heart, blood, gonads, kidneys and dermis of skin -endo- lining of digestive and respiratory tract, liver, pancreas, thymus and thyroid
40
When does air flow into the respiratory system? Out of?
When the gauge pressure inside is LESS than atmosphere (gauge pressure is negative). When gauge pressure is GREATER than atmospheric pressure, air flows out
41
In the lungs, does O2 or CO2 have the highest partial pressure?
O2 is higher than CO2!! Because it promotes CO2 transfer into alveoli
42
In the capillaries, does O2 or CO2 have the highest partial pressure?
CO2 is a bit higher than O2!! Because it promotes O2 into transfer
43
What causes a rightward shift in a hemoglobin oxygen dissociation curve? What does a rightward shift mean?
An INCREASE in CO2 or temperature, and a DECREASE in pH. | -means all of these cause a lower affinity for oxygen
44
How does 2,3-DPG help in high altitudes?
Lowers hemoglobins affinity for oxygen to offload )2 into tissues
45
What is the enzyme that catalyzes the reaction: | H2O + CO2 HCO3- + H+
carbonic anhydrase
46
How does Cl- help with the reaction?
it is exchanged with bicarbonate ions that build up so that the blood is not too negatively charged
47
What will happen when the blood is too acidic?
The body will INCREASE breathing to expel CO2 and raise the pH of blood back up
48
Differentiate between granular and agranular leukocytes.
Granular ones live for a short time because they function nonspecifically against all infections and then die. Agranular cells live long time to watch for repeat infections
49
What is innate immunity? What cells are involved?
It is quick and NONspecific. | Phagocytes: macrophages and neutrophils, and monocytes or eosinophils
50
What are the 2 types of acquired immunity?
B and T cell
51
What is B cell immunity?
Humoral -involves B lymphocytes that make a singe antibody that corresponds to an antigen, then when recognizes it, releases plasma cells and memory B cells
52
What are the different ways that B cells promote destruction of foreign antigen particle?
- phagocytosis via natural killer cells/macrophages - perforate antigen cell - antigen cells to stick together or precipitate - attach to mast cells and then release histamine
53
What is T cell immunity?
Cell mediated -Involves T lymphocytes that also make antibodies, but when recognition happen, produce Killer, Memory and Suppressor T cells
54
Differentiate between MHC class 1 and 2 on cells.
``` MHC class 1 = display antigens from intracellular pathogens via endogenous pathway MHC class 2 = display antigens from extracellular pathogens, so only expressed on phagocytes via exogenous pathway ```
55
What is the difference between positive and negative selection of immunity regulation?
``` (+) = when B and T cells cannot recognize MHC class 1 or 2 cells are destined for apoptosis (-)= when B and T cells respond too strongly to MHC molecules with self-antigens are destined for apoptosis ```
56
What does alpha-amylase do?
Cleaves alpha-1,4 glycosidic bonds of carbohydrates in the mouth
57
Where is pepsin seen in the digestive system? What does it do?
In the stomach, it breaks down proteins
58
What are the 4 types of cells present in the stomach?
1. Mucous cells 2. Chief cells - secrete pepsinogen 3. Parietal cells - secrete HCl 4. G cells - secrete gastrin that stimulates. HCl
59
Digestion happens in the _____ and absorption happens in ________
``` digestion = duodenum absorption = jejunum and ileum ```
60
What does the pancreas secrete in regards to exocrine function?
- bicarbonate (neutralize HCl) - trypsin and chymotrypsin - carboxypolypeptidase (break down proteins) - pancreatic amylase (breakdown carbs) - lipase (break down fats)
61
The large intestine is primarily responsible for..? (2 things)
Water absorption and electrolyte absorption
62
What are the 3 main gastrointestinal hormones?
- Secretin: stimulates pancreas to release sodium bicarbonate to start digestion - Gastric Inhibitory polypeptide: decrease motor activity in the stomach - Cholecystokinin: gall bladder contract and pancreas secretion
63
What are the metabolic functions of the liver?
- Carb metabolism - Fat metabolism - protein metabolism - detoxification
64
When the liver mobilizes proteins/fats for energy, what happens to the pH of blood?
decreases
65
What compounds does the liver store?
- glycogen - blood - vitamins
66
What are the immune functions of the liver?
- Blood filtration | - erythrocyte destruction
67
What forces substances through the glomerulus to bowmans capsule in the kidneys
hydrostatic pressure
68
What happens in the proximal tubule of the nephron?
secretion of H+ and reabsorption of toxins and other molecules
69
The descending loop of Henle has...?
Low permeability to Na+ and high permeability to water
70
the ascending loop of Henle has...?
High permeability to solutes and Impermeable to water
71
What does aldosterone act on and how does it show its affects?
Acts on the distal tubule; it increases the Na/K pumps to INCREASE blood pressure
72
What does anti-diuretic hormone act on and how does it show its affects?
Acts on the end of the distal tubule and the collecting duct; it causes increases reabsorption of water to INCREASE blood volume
73
At the distal tubule, which solutes are moved?
Na and K are reabsorbed, where K, H and HCO3 are secreted
74
The collecting duct is ______to water?
impermeable
75
What part does Calcium play in muscle contraction?
Binds to troponin which moves tropomyosin to expose a site for myosin to bind
76
What part does ATP play in muscle contraction?
Causes myosin to release tropomyosin and stop the power stroke
77
What is oxygen debt?
The need for increased O2 after exercise to metabolize lactic acid build up
78
Why do type 1 (slow twitch) muscle fibres have lots of mitochondria
because produce a lot of energy in an oxidative environment so they can be resistant to fatigue
79
What is the plateau in the heart muscle contraction due to?
slow voltage gated Ca2+ channels; helps the heart from beating too quickly
80
Spongy bone is where____ develop, and compact bone is what holds ____?
- Red blood cells | - yellow marrow (fat cell storage)
81
What are the normal homeostatic levels of calcium in the body?
high concentration outside and low concentration inside cells
82
Which type of joints provides NO movement? SLIGHT movement? MORE movement?
NO - fibrous SLIGHT - cartilaginous MORE - synovial

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