W8: Genetics and Meiosis

Question 1

determine maleness/femaleness

Answer 1

sex chromosomes

Question 2

genetic makeup (DNA sequence)

Answer 2

genotype

Question 3

Expression of a genetic trait/ characteristic (showing)

Answer 3

phenotype

Question 4

genes for the same trait that may have different expressions

Answer 4

alleles

Question 5

individual who has identical alleles for a trait

Answer 5

homozygote

Question 6

individual has different alleles for a trait

Answer 6

heterozygote

Question 7

less potent allele; expressed only in homozygote

Answer 7

recessive

Question 8

allele that masks the expression of a less potent allele

Answer 8

dominant

Question 9

found on both ends of a chromosome

Answer 9

telomere

Question 10

narrowest region of a chromosome

Answer 10

centromere

Question 11

state the number of chromosomes in the nucleus of most human cells

Answer 11

46 (23 pairs, one set from each parent)

Question 12

What is the structure of chromosomes?

Answer 12

Chromosomes are thread-like structures made of DNA and proteins that carry genetic information.

Question 13

What is the function of chromosomes?

Answer 13

They store and transmit genetic information to the next generation during cell division.

Question 14

What is heredity

Answer 14

The passing of genetic traits from parents to offspring through genes.

Question 15

What is a gene?

Answer 15

A segment of DNA that codes for a specific protein and determines a particular trait.

Question 16

What is the difference between phenotype and genotype?

Answer 16

Genotype refers to the genetic makeup of an organism, while phenotype is the physical expression of those genes.

Question 17

What are the stages of meiosis?

Answer 17

A: Prophase I, Metaphase I, Anaphase I, Telophase I, Prophase II, Metaphase II, Anaphase II, Telophase II.

Question 18

What is the difference between mitosis and meiosis?

Answer 18

Mitosis produces two identical daughter cells, while meiosis produces four genetically diverse cells.

Question 19

What is a dominant allele?

Answer 19

An allele that masks the expression of a recessive allele in heterozygous conditions.

Question 20

What is a recessive allele?

Answer 20

An allele whose traits are only expressed in the absence of a dominant allele.

Question 21

What does homozygous mean?

Answer 21

Having two identical alleles for a specific trait.

Question 22

What does heterozygous mean?

Answer 22

Having two different alleles for a specific trait.

Question 23

How are ABO blood groups determined?

Answer 23

By the presence of specific antigens (A, B, AB, or O) on the surface of red blood cells, inherited from parents.

Question 24

What is inheritance?

Answer 24

The transmission of genetic traits from parents to offspring.

Question 25

What are sexual sources of genetic variation?

Answer 25

Crossing over, independent assortment, and random fertilization during meiosis.

Question 26

How is genetics related to maintaining homeostasis?

Answer 26

Genetic traits can influence how the body responds to stress, diseases, and treatment, impacting nursing interventions.

Question 27

What is a Centromere

Answer 27

constricted area of chromosome which links sister chromatids together during cell division, and it divides the chromosome into a short ‘p arm’ and a long ‘q arm’.

Question 28

WHat is a chromatid

Answer 28

2 identical halves of a chromosome which replicate in preparation for cell division.

Question 29

WHat is a telomere

Answer 29

Repetitive stretches of DNA located at the end of linear chromosomes which prevents sticking to other chromosomes..

Question 30

Prophase 1

Answer 30

homologous chromes pair up and form the

Question 31

Once meiosis has been completed, the genetic information of the four new cells is not the same. describe the three sexual processes that facilitate this genetic diversity

Answer 31

1) Genetic recombination (prophase 1) 2) Independent assortment (metaphase 1 3) Random fertilisation

Question 32

Identify in which phase in meiosis I and II could a chromosome separation error occur

Answer 32

Anaphase I or II - chromosomal non0disjunctio, where chromosome pair or chromatid pair not separated - results in wrong number of chromes (or chromatids) in sex cells (eggs, sperm)

Question 33

Identify the major role of meiosis II

Answer 33

split each chromosome ( of two chromatids) into two separate chromatids (=Chromosmes)

Question 34

Name the phase of meiosis in which the independent assortment of paternal and maternal chromosomes take place

Answer 34

- metaphase

Question 35

Name the phase in meiosis in which DNA is exchanged between the paternal and maternal chromosomess

Answer 35

Prophase

Question 36

Name the phase in meiosis in which the DNA is replicated so that each chromosome becomes composed of two chromatids

Answer 36

interphase

Question 37

Why are men more likely to have red-green colour blindess and haemophilia

Answer 37

Women have two X chromosomes, men one. Men have no second chance of inheriting a normal allele if they they have one abnormal allele on their X chromosome