Multicellular Organisms

Question 1

Name the female sex cell in animals

Answer 1

The egg (ovum)

Question 2

Name the male sex cell in animals

Answer 2

The sperm

Question 3

Name the male sex cell in plants

Answer 3

pollen

Question 4

Name the female sex cell in plants

Answer 4

ovule

Question 5

What is fertilisation

Answer 5

The fusion of the nucleii of the haploid gametes of two parents to create a new diploid cell

Question 6

Where does fertilisation take place in animals

Answer 6

In the oviduct

Question 7

Where does fertilisation take place in plants

Answer 7

In the ovary

Question 8

define haploid

Answer 8

A cell with half a full set of chromosomes

Question 9

define diploid

Answer 9

a cell with a full set of chromosomes

Question 10

What is sexual reproduction

Answer 10

reproduction involving two parents that results in offspring with a set of genetic information from each

Question 11

What is asexual reproduction

Answer 11

reproduction involving only one parent resulting in genetic clones as offspring

Question 12

why is variation important

Answer 12

variation is needed so species are able to adapt if their environment changes

Question 13

What are the pros and cons of asexual reproduction

Answer 13

Asexual reproduction is efficient but doesn’t allow a species to adapt

Question 14

what are the pros and cons of sexual reproduction

Answer 14

Time consuming but the species can evolve and adapt

Question 15

what plants use tubers

Answer 15

potatoes

Question 16

what uses runners

Answer 16

strawberries

Question 17

what uses bulbs

Answer 17

garlic

Question 18

what uses plantlets

Answer 18

mexican hat plant

Question 19

what are the two methods of artificial asexual reproduction for plants

Answer 19

cutting - section of plant inserted into soil
grafting - section of plant fitted and bound to root stock

Question 20

what is cell division

Answer 20

a means of increasing the number of cells in an organism

Question 21

why do multicelluar organisms need mitosis

Answer 21

for growth and repair

Question 22

what is contained within two cells produced by mitosis

Answer 22

a complete set of chromosomes and the same genetics

Question 23

step 1 of mitosis

Answer 23

dna is replicatiing itself, appears as fine threads in the nucleus

Question 24

step 2 of mitosis

Answer 24

nuclear membrane begins to break down, chromosones condense and appear as double stranded in nucleus

Question 25

step 3 of mitosis

Answer 25

chromosomes line up at the equator of cell Spindle fibres attach at the centromere

Question 26

step 4 of mitosis

Answer 26

Spindle fibres contract, pulling chromatids apart towards the cell's poles.

Question 27

step 5 of mitosis

Answer 27

nuclear membranes reform around the two separate sets of single stranded chromosomes

Question 28

step 6 of mitosis

Answer 28

cytoplasm divides, two identical daughter cells are left

Question 29

what is a stem cell

Answer 29

an unspecialised cell. the cells in the body of a multicellular organism that carry out mitosis

Question 30

where can you find stem cells

Answer 30

embryos (embryonic) and adult tissue (multipotent)

Question 31

what are the uses of embryonic stem cells

Answer 31

to treat diseases such as Parkinsons or MS and for drugs testing

Question 32

why is the use of embryonic stem cells controversial?

Answer 32

because it involves the destruction of an embryo which many believe is equivalent to murder

Question 33

give an example of a nutrient required for healthy embryo development

Answer 33

Vitamin D for bone development, Vitamin A for eyesight etc.

Question 34

what is a zygote

Answer 34

newly fertilised egg cell

Question 35

blastocyst

Answer 35

16 celled embryo

Question 36

foetus

Answer 36

embryo recognisable as baby

Question 37

what substances can harm an embryo

Answer 37

alcohol can lead to FAS, which can cause learning difficulties, developmental issues and facial abnormalities

Question 38

what do plants need to grow

Answer 38

light heat water

Question 39

nature vs nurture

Answer 39

genetics vs environment

Question 40

continuous variation

Answer 40

measured on a scale of highest to lowest, polygenic eg. height or weight

Question 41

discrete variation

Answer 41

can be measured categorically, due to a single gene eg. eye colour, tongue rolling

Question 42

polygenic vs single gene inheritance

Answer 42

many genes and environment vs one gene

Question 43

genotype

Answer 43

the set of genes inherited

Question 44

phenotype

Answer 44

how the genotype expresses itself physically

Question 45

dominant

Answer 45

the allele that hides the other

Question 46

the allele that is hidden

Answer 46

recessive

Question 47

heterozygous

Answer 47

an individual with a copy of two alleles

Question 48

homozygous

Answer 48

an individual with 2 copies of the same allele

Question 49

alleles

Answer 49

different versions of the same gene

Question 50

gene

Answer 50

a section of DNA that codes for a protein

Question 51

What is another term for homozygous

Answer 51

True breeding

Question 52

2 reasons why predicted ratios are not always achieved

Answer 52

Because fertilisation is a random process, because the number of offspring is not big enough