Unit 2 - S3

Question 1

Animal gametes:

Answer 1

Female - eggs, produced in ovaries
Male - sperm, produced in testis

Question 2

Sperm and egg structure

Answer 2

Sperm- small has a tail to swim, lots are produced
Eggs- large cannot move by itself, very few are produced

Question 3

Male reproductive parts + functions

Answer 3

• bladder = to hold urine
• sperm duct = to move sperm away from testicles
• glands = ??
• penis = carries sperm outside the body
• testis = to produce sperm
• urethra = allows urine to pass outside the body

Question 4

Female reproductive parts + functions

Answer 4

• oviduct = how eggs are transported from the ovary to the uterus
• uterus = where a fertilised egg can grow into a baby
• vagina = where the sperm enters the body and where a baby exits
• ovary = where the eggs are contained

Question 5

Plant gametes:

Answer 5

Female = ovule, produced in the ovary
Make = pollen, produced in the anther

Question 6

Sexual reproduction vs asexual reproductive

Answer 6

Sexual reproduction = 2 parents
Asexual reproduction = 1 parent

Question 7

What are the stages of reproduction in plants

Answer 7

1) pollination
2) fertilisation
3) germination

Question 8

Parts of a wind pollinated plant + functions:

Answer 8

Bract -
Anther -
Stigma -

Question 9

Parts of an insect pollinated plant + functions:

Answer 9

Carpels ( female parts ):
~ stigma - part of the flower in which pollen grains are deposited
~ style
~ ovary - the female part of the plant that contains ovules
Stamen ( male parts):
~ anther - the top part of the stamen, they produce pollen
~ filament
Other parts:
~ sepal - protect the developing flower
~ nectary - produce nectar to attract insects
~ petal - usually brightly coloured to attract insects

Question 10

What is a haploid?

Answer 10

One set of chromosomes

Question 11

What is a zygote ?

Answer 11

The first cell made of the sperm and the egg

Question 12

What is a diploid?

Answer 12

Two sets of chromosomes

Question 13

What is germination ?

Answer 13

A seed growing into a plant

Question 14

What is a seed?

Answer 14

A fertilised plant egg

Question 15

What is pollination ?

Answer 15

The transfer of pollen grains from the anther (male part) to the stigma (female part)

Question 16

How many chromosomes are found in humans?

Answer 16

46 total ( 23 pairs )

Question 17

What are alleles ?

Answer 17

Different forms of the same type of gene ( eg the gene for blue eyes and the gene for brown eyes are alleles )

Question 18

What does dominant allele mean?

Answer 18

It is the allele that will show up in the organism’s appearance

Question 19

What does the recessive allele mean?

Answer 19

It is the allele that will still be passed on but is hidden by the dominant one ( probably won’t show up in an organisms appearance )

Question 20

What does genotype mean?

Answer 20

The alleles you have for a particular characteristic or feature

Question 21

What does phenotype mean?

Answer 21

The trait or characteristic that shows in your appearance

Question 22

What does heterozygous mean?

Answer 22

When an organism inherits 2 different alleles of a gene

Question 23

What does homozygous mean?

Answer 23

When an organism inherits 2 identical alleles of a gene

Question 24

What is homeostasis ?

Answer 24

The control of an internal environment

Question 25

What is Osmoregulation ?

Answer 25

The control of blood-water content

Question 26

What is negative feedback?

Answer 26

The mechanism which can detect changes in the body and return them to tolerable levels

Question 27

Stages of Osmoregulation:

Answer 27

1: the osmoreceptors in the hypothalamus of the brain detect changes in the water concentration in your body 2: a message is sent to the pituitary gland ( control centre ) 3: the pituitary gland gland releases a hormone called ADH 4: the kidney reabsorbs water according to the level of ADH produced

Question 28

What are the 2 ways to control blood glucose concentration?

Answer 28

Homeostatic regulation ( controlled by the pancreas ) Stress response ( controlled by the brain )

Question 29

How is glucose stored and where?

Answer 29

Insulin is used to turn it into glycogen and it is stored in the liver

Question 30

How is glycogen released from the liver?

Answer 30

Glucagon turns it into glucose so it can be released in the bloodstream and got to muscles

Question 31

Stages of homeostatic regulation of BGC:

Answer 31

1: eating sugar 2: BGC increases 3: receptors in pancreas detect this change 4: the pancreas releases insulin which converts glucose into glycogen 5: glycogen is stored in the liver 6: BGC decreases and returns to normal

Question 32

What are endotherms?

Answer 32

Their body temperature does not change with the external environmental temperature ( eg mammals and birds)

Question 32

Stages of stress response to change in BGC:

Answer 32

1: receptors in the brain detect a stressful situation/activity 2: a message is sent to the adrenal gland which releases adrenaline 3: adrenaline converts glycogen to glucose 4: glucose is released from the liver 5: BGC increases in preparation for the situation/activity ( fight or flight )

Question 33

What are ectotherms?

Answer 33

Their body temperature does change with the external environmental temperature ( fish, reptiles and amphibians)

Question 34

How does thermoregulation work?

Answer 34

Thermoreceptors are found in the hypothalamus ( control centre ) which sends messages ( nerve impulses ) to the effectors ( skin and muscle )

Question 35

What does the skin do when the body is too hot?

Answer 35

- the skins sweat glands release sweat which evaporates due to body heat - vasodilation

Question 36

What is vasodilation?

Answer 36

The surface blood capillaries can dilate to allow more blood to flow to the surface of the skin allowing heat to be lost

Question 37

What does the skin do when the body is too cold?

Answer 37

- vasoconstriction - goose bumps - shivering

Question 38

What is vasoconstriction?

Answer 38

The surface blood vessels can contract to reduce blood flow to the surface of the skin, this allows heat to be retained

Question 39

What are goose bumps?

Answer 39

The hair erector muscles on the surface of the skin contract to raise hair and trap a layer of air which acts as an insulant

Question 40

What is shivering?

Answer 40

When body muscles rapidly contract and relax which generates heat

Question 41

What are the uses of plants?

Answer 41

Food Medicine Raw materials

Question 42

Examples of food:

Answer 42

Potatoes, bananas, strawberries

Question 43

Examples of medicine:

Answer 43

Morphine(from poppies), aspirin (from willow trees),belladonna ( from nightshade plants)

Question 44

Examples of raw materials:

Answer 44

Wood(from trees), paper(from trees), cotton(from cotton plants)

Question 45

How to have a healthy lifestyle:

Answer 45

Eat more fruit and veg, eat less fats+sugars, exercise more,avoid smoking and drinking alcohol

Question 46

What is the structure of a seed + functions?

Answer 46

- an embryo = a small undeveloped plant - food store = to provide energy for the growth of the embryo - a seed coat = round the outside which protects the seed until it is ready to grow

Question 47

Where does fertilisation happen?

Answer 47

The oviduct

Question 48

Describe the process of fertilisation in plants:

Answer 48

The nucleus of the pollen grain then travels down the pollen tube into the ovary where it fuses with the nucleus of the egg cell