bio paper 2 - worst questions

Question 1

how do we know if individuals are members of the same species

Answer 1

if they can breed with each other and produce fertile offspring

Question 2

what is the process of speciation (4)
and who bascially made this theory

Answer 2

1. populations of the same species experience different environments
2. populations becoming isolated
3. populations exhibit genetic varition
4. natural selection happens different creating 2 distinct species
   alfred wallace

Question 4

what are two things that support the theory of evolution

Answer 4

antibiotic resistant bacteria
fossils

Question 5

what are the 3 causes of a fossil being formed (fossilisation)

Answer 5

• where decay isn’t possible (peat bogs, very acidic and glaciers, very cold)
• hardening soft materials
• mineral replacement

Question 6

3 ways to reduce new antibiotic resistant strains

Answer 6

1. doctors only prescrbing for serious illnesses and not for viral infections
2. patients must finish their course of antibiotics
3. use of antibiotics in agriculture should be restricted

Question 7

what is evolution

Answer 7

is the slow change in the inherited characterists of groups of biological populations over many generations

Question 8

whats the order of the nervous system
some really smart rats move elegantly right

Answer 8

stimulus, receptor, sensory neurone, (synapse) relay neurone (synapse), motor neurone, effector (gland/ muscles), response

Question 9

what is a hormone

Answer 9

chemical messenger that’s produced by a gland
transported in the bloodstream to target organs

Question 10

how do hormones react when theres a low blood sugar vs a high blood sugar in the body

Answer 10

LBS - stimulates the pancreas to release glucagon, which converts glycogen into glucose
HBS - stimulates the pancreas to release insulin, which helps the cells absorb glucose lowering the blood sugar levels

Question 11

how does homeostasis prevent the body from overheating during excerise (3)

Answer 11

1. blood vessels near the skin dilate, increasing the blood flow to the skin
2. more heat lost through radiation / convection
3. sweating increase the evaporation of sweat cools down body

Question 13

explain how the body maintains water balance when a person is dehydrated (3)

Answer 13

• ADH is released by pituitary gland, this increases water reaborption
• ADH makes kidney tubules more permeable so more water is reabsorbed
• less urine production

Question 14

what an pro of the binomial system for naming organisms

Answer 14

universal system understood globally, reduces confusion

Question 15

explain how trees are in the carbon cycle

Answer 15

trees absorb carbon d during photosynthesis
carbon stored as biomass (like wood and leaves)
trees release carbon d during respiration or decomposition

Question 16

2 reasons why no all biomass is transferred to the organism at the top of a food chain

Answer 16

lost through respiration (when its used for movement)
undigested material lost in waste (faeces)

Question 17

why is meiosis necessary for sexual reproduction rather than mitosis

Answer 17

meiosis produces gametes with 23 chromosomes (haploid)
this allows fertilisation to restore full number of chromosome (diploid)

Question 18

explain each pro of each type of reproduction for plants

Answer 18

sexual - increases genetic variation, helping species adapt
asexual - produces large numbers of offsprings quickly, so more likely to survive

Question 19

what does oestrogen do in menstrual cycle
what produces oestrogen

Answer 19

causes uterus lining to thicken
and stimulates the release of LH for ovulation
- ovaries

Question 20

what does progesterone do in menstrual cycle
what produces progesterone

Answer 20

maintains the unterus lining for implantation
stops LH and FSH
- ovaries

Question 21

what does LH do in menstrual cycle
what produces LH

Answer 21

triggers ovulation
causes follicles in ovary to make progesterone
- pituitary gland

Question 22

what does FSH do in menstrual cycle
what produces FSH

Answer 22

matures the egg
stimulates oestrogen production
- pituitary gland

Question 23

what are the 3 parts of DNA

Answer 23

sugar molecule, nitrogenous base, phosphate group

Question 24

describe and explain the effects of temp on the rate of decomposition (5)

Answer 24

1. as temp increase, decomposition increases
2. microorganisms release enzymes that break down organic material
3. enzymes work faster in higher temps due to increased kinetic energy
4. if temp too low - enzymes work slowly and decomposition rate reduces
5. if temp too high - enzymes denature stopping decomposition

Question 25

whats a con of embryo screening

Answer 25

some believe selecting embryos is unethical since it may cause the destruction of embryos carrying the disorder

Question 26

describe process of adult cell cloning

Answer 26

-nucleus is removed from adult body cell -this nucleus is inserted into an egg cell that has had its -nucleus removed -egg cell is stimulated to divide by an electric shock -embryo develops and is implanted into a surrogate mother