module 5: systems of life

Question 1

what are the 4 features of exchange surfaces

Answer 1

1. large SA:V ratio
2. thin barrier
3. concentration gradients
4. selectively permeable

Question 2

how do you maximise gas exchange

Answer 2

-large SA:V ratio
-maximise the particle pressure

Question 3

what is the equation for partial pressure

Answer 3

P(total)=Pressure(a)+pressure(b)+pressure(c)…..

Question 4

what enviroment is harder for gas exchange

Answer 4

water because it is more denser and harder to move around in, therefore it is harder for gas exchange

Question 5

how do plants undergo gas exchange

Answer 5

through photosynthesis and cellular respiration

Question 6

how do insects undergo gas exchange

Answer 6

-they have gates that can be closes
- when they are open they allow for gas exchange
- when they are closed they prevent gas exchange

Question 7

how do crustaceans undergo gas exchange

Answer 7

crabs have internal gills
-this is an open system

Question 8

how do fish undergo gas exchange

Answer 8

-have internal gills
- this is a closed system
- they are controlled by the opening and closing of their mouth

Question 9

is blue blood oxygenated

Answer 9

no

Question 10

is red blood oxygenated

Answer 10

yes

Question 11

what do alveoli do

Answer 11

they fill up with air

Question 12

what causes the alveoli not to collapse

Answer 12

due to the lightless of the lung tissue

Question 13

what happens to CO2 and O2 in the alveoli

Answer 13

• O2 is diffused out into the capillaries
• co2 is diffuses into the aveolius

Question 14

why is BPG bad

Answer 14

it binds to hemoglobin instead of oxygen, changes the shape of haemoglobin

Question 15

what are the factors that can influence hemoglobin dissociation

Answer 15

• high co2
  increased acidity
• bpg

Question 16

what is the haldane effect

Answer 16

• CO2 binds to haemoglobin
  -haemoglobin not carries o2 has a higher affinity for CO2
• the haldane effect facilitates the removal for CO2 at tissues with low partial pressure of o2

Question 17

what molecule do muscles to have to store oxygen

Answer 17

myoglobin

Question 18

what is myoglobin

Answer 18

• a protein that increases oxygens affinity
• binds to oxygen at low partial pressure
• used when we exercise

Question 19

how are marine animals able to hold their air for so long

Answer 19

increased myoglobin and haemaglobin
- reduce their heart rate
reduce blood flow to their organs

Question 20

how does COVID 19 affect the lungs

Answer 20

• Virus enters lungs
• Virus binds to alveolar wall cells and injects its RNA
• Infected cell produce many copies of the virus
  -Alveolar cell destroyed virus particles released and infect neighbouring cells

Question 21

what does the modella do

Answer 21

• it is apart if the brian that detects changes in the partial pressure of O2 and CO2 and pH in the cellubrial fluid

Question 22

what is a chemoreceptors

Answer 22

chemical receptor that is sent to the breathing control center (modulla)

Question 23

where are these chemoreceptos found in the lungs

Answer 23

-aorta
-modulla
-carotic bodies

Question 24

what is the importance for sexual reproduction

Answer 24

produced offspring that are genetically different to their parents and increases the populaton of a species

Question 25

why is reproduction expensive

Answer 25

• competition for mates and males
  production of gametes
  production of pheromones

Question 26

what protein establishes maleness

Answer 26

-SRY protein

Question 27

the absence of SRY

Answer 27

is female

Question 28

what are the 3 major sex hormones that are produced by the gonads

Answer 28

-Oestrogen
-Androgens
-Progesterone

Question 29

what secondary sex characteristics of testosterone

Answer 29

deeper voice
adams apple
public hair
increases sex drive
muscle growth

Question 30

what are the secondary sex characteristics for oestrogen

Answer 30

-breast development
public hair increases sex drive

Question 31

what is Oogenesis

Answer 31

Oogenesis is the process by which female germ cells develop into mature eggs

Question 32

what are the steps of Oogenesis

Answer 32

Proliferation
Primary oocyte formation:
Growth and maturation of the primary follicle:
Secondary oocyte formation:
Completion of meiosis II

Question 33

what happens at Proliferation

Answer 33

Oogonia undergo mitosis to increase in number during fetal development.

Question 34

what happens at Primary oocyte formation:

Answer 34

Some oogonia differentiate into primary oocytes, which become surrounded by follicular cells to form primordial follicles.

Question 35

what happens at Growth and maturation of the primary follicle

Answer 35

The primary oocyte and follicular cells grow, and the follicle becomes a primary follicle. The primary oocyte undergoes DNA replication but remains arrested in meiosis I.

Question 36

what happens at Secondary oocyte formation

Answer 36

At puberty, some primary follicles mature, and the primary oocyte completes meiosis I, producing a secondary oocyte and a polar body

Question 37

what happens at Completion of meiosis II

Answer 37

If the secondary oocyte is fertilized by a sperm cell, it completes meiosis II, producing a mature ovum and another polar body. The ovum and sperm fuse to form a zygote