Variation & Plants - Unit 2

Question 1

What is the definition of variation ?

Answer 1

Differences that occur between individual members of a species called variation

Question 2

What is the type of inheritance for discrete variation?

Answer 2

Single gene (where measurements fall in to distinct groups)

Question 3

What is the type of inheritance for continuous variation?

Answer 3

Polygenic (range of values)

Question 4

What do genes do?

Answer 4

code for proteins

Question 5

What are Alleles

Answer 5

Different forms of the same gene

Question 6

What types of alleles always show up in the appearance of organism and what alleles don’t?

Answer 6

Dominant (RR) , Recessive (rr)

Question 7

What is a genotype?

Answer 7

The alleles an organism carriers for a particular characteristic

Question 8

What does it mean if an organism is homozygous?

Answer 8

The alleles are the same

Question 8

What is a phenotype?

Answer 8

The physical features of a characteristic

Question 9

What does it mean if an organism is heterozygous?

Answer 9

The alleles are different

Question 10

How come some predicted ratios are not correct?

Answer 10

Fertilisation is a random process that contains an element of choice

Question 11

What are the plants transport organs?

Answer 11

Leaves, stem, roots

Question 12

what is the structure of a leaf

Answer 12

Waxy Cuticle ,Upper Epidermis,Palisade mesophyll ,Spongy mesophyll ,Lower epidermis ,Guard cells ,Stomata

Question 13

What are the structural features and function of the xylem?

Answer 13

Dead, Lignin rings. Once water is absorbed its carried upwards by the xylem towards leaves for photosynthesis

Question 14

What are the structural features and function of the phloem

Answer 14

Alive, next to xylem tissue. Carries sugars around the plant up and down

Question 15

What is transpiration? (short)

Answer 15

the evaporation of water into the atmosphere from leaves of plants

Question 16

What is transpiration? (long)

Answer 16

Water moves from the roots of a plant to the leaves
Water is vital for the transport of minerals within a plant and for photosynthesis
Water is lost through the stomata on the underside of the leaf
Root hair cells increase surface area for the absorption of water
Water moves into root hair cells by mitosis
Water moves through stem and leaves through xylem
Water exits through stomata in leaves

Question 17

How can you measure the rate of transpiration?

Answer 17

Bubble potometre

Question 18

What are 4 things that increase the rate of transpiration?

Answer 18

increase in temp, increase in wind speed, increase in surface area, decrease in humidity