d3.2 (inheritance) Flashcards

1
Q

define zygote

A

the diploid cell produced at fertilization when gametes fuse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

where are male gametes found in flowers?

A

in pollen grains on the flower anther

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

where are female gametes found in flowers?

A

inside the ovules of the flower ovary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

watch a video on mendel’s pea plants

A

-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

define phenotype plasticity

A

an organism’s ability to change its phenotype in response to environmental conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

example of phenotype plasticity: butterworts (plant)

how does their morphology differ in nutrient rich vs poor conditions?

A

rich : large leaves for photosynthesis
poor : smaller leaves for capturing & digesting insects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

ways phenotype plasticity manifests itself in animals (3 ways with example of garter snakes)

A

coloration = to absorb/reflect light to maintain body temperature

metabolic rate = varies with temp, affecting activity level, feeding freq & energy use

reproductive timing = warmer temps may accelerate development & increase freq of reproductive cycled

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

define autosomal (for genetic diseases) & effect pattern

A

the gene is located on an autosome, so males and females are equally affected

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

define sex-linked (for genetic diseases) & effect pattern

A

the gene is located on a sex chromosome, resulting in a different pattern of inheritance in males and females

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

2 main examples of sex-linked genetic diseases

A

red-green colour blindness

haemophilia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what does disease phenylketonuria (PKU) cause?

A

phenylalanine from the diet is not processed effectively as an allele that codes for a non-functioning phenylalanine hydroxylase is present (may cause brain damage if excessive amounts of phenylalanine are taken in)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is the treatment for PKU?

A

a diet containing little or no phenylalanine (an amino acid in plant and animal foods, such as meat, eggs, fish, and soy products)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is a SNP?

A

single nucleotide polymorphism (a variation at a single position in a DNA sequence)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

if a SNP occurs within a gene, then the gene is described as having what?

A

more than 1 allele

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

an example of a gene with multiple alleles in the gene pool is called the “s-gene”. where is it found & how many known alleles are there?

A

the gene pool of many tree fruit crops
over 50 known alleles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

define cultivar

A

a variety of a plant for which people have selected for desired traits and which retains those traits when propagated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

in species with the s-gene, what process is necessary to achieve sexual reproduction? explain how this works

A

cross-polination

during pollination, if a pollen lands on the stigma of a flower with the same allele of the s-gene, the pollen is rejected and fertilization will not occur.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are the 3 ABO blood type alleles?

A

Iᴬ , Iᴮ , i

19
Q

how do the 3 different blood type alleles each alter the glycoprotein on the red blood cell membrane?

A

Iᴬ = adds molecule acetylgalactosamine
Iᴮ = adds molucule galactose
i = does not add anything

20
Q

sometimes one allele is not completely dominant over the other alleles of a gene– what is this called? what type of phenotype is caused?

A

incomplete dominance
an intermediate heterozygous phenotype

21
Q

example of incomplete dominance (petals)

A

in snapdragons, colour is influenced by a gene with 2 alleles, red (Cᴿ) and white (Cᵂ). upon cross pollination between two homozygous parents with each of these two alleles, offspring will have pink flowers (CᴿCᵂ)

22
Q

example of codominance (coat colour)

A

roan coat color in many organisms is the result of having red hair (Cᴿ) interspersed with white hairs (Cᵂ)

23
Q

what typically triggers male development? why? what formation is initiated?

A

presence of a Y chromosome, due to SRY gene, initiates testes formation

24
Q

deducing patterns of inheritance from pedigree charts
the trait skips generations = ?
the trait found much more in males = ?

A

recessive, sex-linked

25
features of discrete variation within a species x3 & examples
phenotypes that can be put into distinct qualitative categories with no intermediates between them influenced by only one or a few genes not significantly influenced by the environment i.e. blood type, medel pea plant stem height
26
features of continuous variation within a species x3 & examples
phenotypes that vary along a quantitative continuum with a range of phenotypes possible results from complex interaction between many different genes (“polygenic”) the environment influences the expression of the phenotype i.e. human height & skin colour
27
why do mendel's pea plants have stem height as an example of discrete variation? what controls it to make it discrete?
pea plants were either tall or dwarf, with no intermediate heights the pea plant stem height gene, Le, codes for a protein that is required for the production of a plant growth hormone called gibberellin
28
how and where is melanin produced? how many genes are involved in human skin colouration?
made within small membrane–bound packages called melanosomes within skin cells. 169 genes are involved
29
how does environment affect skin colour?
exposure to sunlight stimulates melanocytes to produce additional melanin. melanin absorbs UV radiation so that it does not penetrate deep into the skin
30
what impact can too much UV exposure do (adaptation of more melanin in skin)? what impact can too little UV exposure do (adaptation of less melanin in skin)?
too much = folate deficiency → neurological abnormalities in fetal development too little = vitamin D deficiency → reduced Ca2+ absorption and brittle bones
31
read over d3.2.16 save my exams notes
-
32
define linked vs unlinked genes
linked: genes located close to each other on the same chromosomes (genes move together through meiosis) unlinked: independently assorted; genes on different chromosomes
33
define dihybrid cross
a genetic cross between two individuals with two observed traits that are controlled by two unlinked genes
34
in mendel's pea plants, how many possible unique gametes created from a RrYy plant (round yellow)?
4: RY, Ry, rY, ry
35
do a few practice dihybrid cross punnet grids
-
36
what is linked gene notation?
look up image
37
watch a video on linked genes
-
38
do a few practice linked genes punnet grids
-
39
define recombinant
an offspring with a different combination of alleles than those found in either parent
40
what are recombinants the result of?
the processes of meiosis that lead to genetic variation (i.e. independent assortment of unlinked genes during metaphase 1 and/or crossing over between linked genes during prophase I)
41
new combinations of alleles of genes on the same chromosome can be produced during what phase?
prophase I of meiosis
42
how does distance between linked genes change the probability of recombinant offspring?
the greater the distance between two genes, the more likely a crossover will occur between them
43
do a few practice of crossing over of linked genes punnet grids
-