Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology🧬🦠 > Component 3: Requirements for Life > Flashcards

Component 3: Requirements for Life Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

How can oxygen enter a plant?

A

Through the stem and roots by diffusion or through the leaves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How can gases enter a leaf?

A

Diffuse through the stomata down a concentration gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Give 4 features of a leaf that provide an advantage for gas exchange

A

1) Large surface area
2) Thin
3) Air space in the spongy mesophyll
4) Stomatal pores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

In a plant, what is the cuticle?

A

The waxy covering of the leaf that helps reduce water loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the stomata?

A

Small pores that mostly occur on the lower surfaces of leaves. Each pore is surrounded by two guard cells. Stomata can open and close for gas exchange depending on the needs of the plant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How does a stomata open and close?

A
  • If water enters a cell tgey become turgid and swell, the pore opens
  • If water leaves the guard cells, they become flacid and the pore closes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is homeostasis?

A

The maintenance of a constant internal environment and the ability to return to a set point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Identify 3 Homeostatic control systems

A

pH
Temperature
Water Potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where are receptors for osmoregulation found?

A

Osmoreceptors in the Hypthalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is ADH and where is it produced?

A

Anti-Diuretic Hormone (reduces urniation)

Produced in the Posterior pituitary gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Give 2 functions of the Kidney

A
  • Excretion of Nitrogenous metabolic waste from the body

- Osmoregulation (balance of water and dissolved solvents)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In what part of the Kidney is the Bowman’s Capsule found?

A

The Cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

In what part of the kidney is the Loop of Henle found?

A

The Medulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where does ultrafiltration take place?

A

In the Glomerulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is Ultrafiltration and what is the product called?

A

Filtration under pressure which separates small soluble molecules from the blood.
- Glomerular Filtrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is selective re absorption?

A

The process by which useful products are re absorbed back into the blood e.g glucose, water and Na+ Cl- ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe the cells of the proximal convoluted tubule and how they are adapted for selective re absorption

A
  • Cuboidal epithelial cells

large surface area(microvilli), many mitochondria(ATP for active transport) and close to capillaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What happens to the concentration of the glomerular filtrate as it passes on from the Proximal convoluted tubule?

A
  • Conc increases in the descending limb due to re absorption of water
  • Conc decreases in ascending limb as ions are re absorbed
  • Conc increases in collecting duct as more water is re absorbed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Where is the vasa recta found and what is it’s function?

A
  • surrounds the loop of henle

- water diffuses into the vasa recta and it provides O2 and glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How does the body work to reduce a high blood concentration?

A
  • More ADH is released, making the walls of the collecting duct more permeable
  • More H2O is reabsorbed into the blood
  • A lower volume of High concentration urine is produced
  • Blood concentration returns to normal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How does ADH make the walls of the Collecting duct more permeable?

A

Aquaporins, found in vesicles, move towards the cell membrane of the collecting duct to allow more water to pass through

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Give 5 common causes of kidney failure

A
  • Diabetes
  • High blood pressure
  • Auto immune disease
  • Infection
  • Crush injuries
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Give 4 treatments for kidney failure

A
  • Drugs to reduce blood pressure
  • Lower protein diet
  • Dialysis
  • Kidney transplant
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Briefly explain how dialysis works

A

Blood is taken from an artery and passes through a dialyser. Diffusion and Osmosis occurs across a selectively permeable membrane to remove urea and other small molecules. The blood is then returned to the body through a vein.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Why are anticoagulants used in dialysis?

A

To prevent the blood clotting when coming into contact with a foreign surface.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Why are immunosuppressant drugs used?

A

Reduce the risk of infection or rejection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the excretory product of:

  • Fish
  • Birds
  • Mammals
A
  • Ammonia
  • Uric acid
  • Urea
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Why do desert animals have a long loop of henle?

A

To allow for more reabsorption of water into the blood - reduces water loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is metabolic water?

A

Water produced from the breakdown of food and respiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What would you expect to find about the loop of henle in organisms in hot/dry environments?

A

long

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is an Autotrophic organism?

A

An organism that uses simple inorganic materials to produce its own food

32
Q

Name 2 types of Autotroph

A

Photo autotrophic

Chemo autotrophic

33
Q

What is Photo-autotrophic nutrition?

A

Light is used as an energy source to perform photosynthesis

34
Q

What is chemo-autotrophic nutrition?

A

The use of energy from chemical reactions (chemosynthesis)

35
Q

What are heterotrophic organisms?

A

cannot produce their own food, consume autotrophs or other organisms that have consumed autotrophs.

36
Q

Name 3 types of heterotrophic nutrition

A

1: saprotrophic
2: parasitic
3: holozoic

37
Q

What is saprotrophic nutrition?

A

Feed on dead or decaying matter.

Enzymes are secreted into the food for extracellular digestion, soluble products are absorbed into the organism.

38
Q

What is parasitic nutrition?

A

Obtaining nutrition from another organism, the host, in a way that harms the host.

39
Q

What is holozoic nutrition?

A

Ingest, digest and egest food. Food is processed internally in a specialised digestive system.

40
Q

What is peristalsis?

A

Longitudinal and circular muscles in the gut wall contract and relax, creating a wave of contractions that push food along.

41
Q

Name the 2 parts of the small intestine

A

ileum

duodenum

42
Q

Name 5 parts of the gut wall

A 
Lumen
Serosa
Muscle
Mucosa
Submucosa
43
Q

What is the function of the serosa?

A

Tough connecting tissue that protects the gut wall.

44
Q

What is the function of the mucosa and submucosa?

A

Mucosa : secretes mucus for lubrication and can secrete enzymes
Submucosa : Contains blood/lymph vessels and nerves.

45
Q

What is the function of the colon?

A

Absorption of water

46
Q

What is the function of the small intestine?

A

Digestion and absorption

47
Q

How is the small intestine adapted for absorption?

A

Villi provide a large surface area
Mitochondria present for active transport
Epithelium only one cell thick

48
Q

Why must herbivores have different dentition to carnivores?

A

Cellulose and lignin in plant cell walls make them tough so the herbivore teeth must be adapted to thoroughly grind plants before digestion

49
Q

Give 2 features of a herbivores dentition that are different to carnivores

A
  • Leathery pad on upper jaw

- Interlocking molars produce a grinding motion as the lower jaw moves from side to side

50
Q

Give 3 features that distinguish carnivore dentition from a herbivores

A
  • Sharp incisors to grip and tear muscle from bone
  • Cannot move jaw from side to side but can open wider
  • Jaw muscles are powerful and well developed to grip prey and crush bone
51
Q

What is the difference between an open and closed circulatory system?

A

Open: tissues are bathed directly in blood (no blood vessels)
closed: blood is transported round the body in blood vessels

52
Q

Why is double circulation more effective?

A

Blood can be pumped round the body at a higher pressure

53
Q

Describe an artery.

A
  • Carries blood away from the heart

- Has thick, muscular walls that can withstand the bloods high pressures straight from the heart

54
Q

How are veins different to arteries?

A
  • carry blood TO the heart
  • have a larger lumen and thinner walls
  • have semi lunar valves that prevent back flow
55
Q

How are capillaries adapted for gas exchange?

A
  • Form a network that penetrates all organs and tissues in the body
  • 1 layer of single epithelial cells on a basement membrane
  • pores between cells to allow for easier diffusion
  • small diameter and blood flow slows to allow for maximum gas exchange
56
Q

Describe the composition of the heart.

A

Made up of cardiac muscle which does not tire and produces a myogenic contraction. Muscle is thicker on the left side of the heart as it must pump blood through the aorta all through the body. The right side just pumps blood through the pulmonary arteries to the lungs.

57
Q

Name the 3 stages of the cardiac cycle.

A

Atrial systole
Ventricular systole
Diastole

58
Q

What happens during atrial systole?

A

The atria walls contract and blood pressure in the atria increases, this pushes blood through the bicuspid and tricuspid valves into the ventricles.

59
Q

What happens during ventricular systole?

A

The ventricle walls contract and blood pressure increases, forcing blood through the semi lunar valves of the pulmonary artery and aorta, sending blood around the body.

60
Q

What happens during diastole?

A

Ventricles and atria relax, volume increases and so pressure decreases. Blood flows back into the atria so the cycle can start again.

61
Q

Explain how valves work and name two valves.

A
  • Prevent backflow of blood by closing when blood pressure is high.
    Bicuspid (L) and tricuspid (R) valves separate the atria and ventricles.
    Semi-lunar valves are found at the base of the pulmonary artery/aorta and in veins.
62
Q

Explain how a heartbeat is produced.

A

The sino-atrial node sends an electrical stimulation across the atria, causing them to contract.
then…
The atrio-ventricular node sends an electrical stimulation across the ventricles causing them to contract.

63
Q

Describe the composition of blood

A

45% cells, 55% plasma

64
Q

Describe the function and structure of red blood cells (4)

A
  • contain the pigment haemoglobin
  • Transport O2 from the lungs to respiring tissue
  • Biconcave shape to increase surface area
  • No nucleus, more room for Hb
65
Q

Describe the composition and function of plasma

A

90% water

- Distributes food molecules (glucose, vitamins), hormones and plasma proteins

66
Q

How does haemoglobin carry oxygen around the body?

A

1 Hb molecule has 4 haem groups that each contain an Fe2+ molecule, 1 oxygen molecule can bind to each iron ion.

67
Q

What is cooperative binding?

A

Once the first O2 molecule has bonded to haemoglobin, the shape of the haemoglobin changes to more easily bind to the next O2

68
Q

Explain how haemoglobins affinity for oxygen changes.

A

Affinity for O2 is highest in the lungs, where it associates readily. At the respiring tissue Hb dissociates from O2 by changing its shape.
Affinity is higher at high partial pressures as there is more oxygen present in relation to other gases.

69
Q

What is the chloride shift?

A

Cl- ions diffuse into red blood cells to balance the outflow of HCO3- ions.

70
Q

What is formed when haemoglobin binds to H+?

A

Haemoglobinic acid

71
Q

Give 4 features of an exchange surface.

A
  • Large SA to volume ratio
  • Short diffusion pathway
  • Permeable
  • Mechanism to produce a concentration gradient
72
Q

How do Unicellular organisms exchange gases?

A

Can absorb O2 across the cell membrane rapidly as they have a large surface area and short diffusion pathway

73
Q

What disadvantages do cartilaginous fish have?

A
  • Do not have a mechanism to force water over the gills so can’t stop swimming
  • Parallel flow of blood and water so can only reach 50% O2 saturation in blood
74
Q

How do Bony fish force water over the gills?

A

The operculum produces pressure differences in the mouth cavity

75
Q

What is the advantage of a counter current flow in bony fish?

A

Allows for up to 80% O2 saturation as a concentration gradient is maintained.

Biology🧬🦠 (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions