Reproduction

Question 1

what is asexual reproduction?

Answer 1

only involves one parent, organisms are genetically identical to each other and their parent, rely on mutations for variations in DNA.

Question 2

Where is DNA stored?

Answer 2

the cell’s nucleus contains DNA. DNA is wound up tighly into chromosomes. Chromosomes contain many genes.

Question 3

What is a gene?

Answer 3

a length of dna is the ‘instruction’ how to make a protein - also called a gene

Question 4

what is a diploid cell?

Answer 4

Diploid is a cell or organism that has paired chromosomes, one from each parent.

Question 5

what is a haploid cell?

Answer 5

(sex cells)
1 copy of each chromosome,
gametes (reproductive cells) are haploid

Question 6

what is sexual reproduction?

Answer 6

production of new living organisms involving two parents,

Question 7

what are gametes?

Answer 7

an organisms reproductive cells, they are made by meiosis

Question 8

what is mitosis?

Answer 8

a process where a single cell divides into two identical daughter cells (cell division)

Question 9

what is meiosis?

Answer 9

form of cell division which produces four non-identical, haploid sex cells or gametes

Question 10

advantages of sexual reproduction

Answer 10

produces variation in offspring, disease is less likely to effect entire population, species can easily adapt to new enviroments.

Question 11

advantages of asexual reproduction

Answer 11

only one parent is needed, population can increase rapidly

Question 12

disadvantages of sexual reproduction

Answer 12

time and energy are needed to find a mate, not possible for to reproduce individally, slower

Question 13

disadvantages of asexual reproduction

Answer 13

does not lead to variation, disease may effecy entire population, cannot adapt easily to changes in enviroment.

Question 14

What is sexual reproduction?

Answer 14

Sexual reproduction involves the fusion of two gametes (egg and sperm) from two parents, resulting in offspring with genetic variation.

Question 15

What is asexual reproduction?

Answer 15

Asexual reproduction involves only one parent, and offspring are genetically identical to the parent.

Question 16

Give an example of an organism that reproduces sexually.

Answer 16

Humans, animals, and most plants reproduce sexually.

Question 17

Give an example of an organism that reproduces asexually.

Answer 17

Bacteria and some plants (e.g., strawberries) reproduce asexually.

Question 18

What is a bacterial growth curve

Answer 18

A bacterial growth curve is a graph that shows how the number of bacteria in a population changes over time.

Question 19

Name the four phases of the bacterial growth curve.

Answer 19

The four phases are lag phase, log phase, stationary phase, and death phase.

Question 20

What happens in the lag phase of bacterial growth?

Answer 20

In the lag phase, bacteria are adjusting to their environment and not dividin

Question 21

What happens in the log (exponential) phase of bacterial growth?

Answer 21

In the log phase, bacteria are dividing at a rapid rate, leading to exponential growth.

Question 22

What is binary fission?

Answer 22

Binary fission is the process by which bacteria and some other organisms reproduce asexually, where one cell divides into two identical daughter cells.

Question 23

What happens to the DNA during binary fission?

Answer 23

The DNA is replicated, and then the cell splits into two, with each new cell receiving a copy of the DNA.

Question 23

Is binary fission a form of sexual or asexual reproduction?

Answer 23

Binary fission is a form of asexual reproduction.

Question 23

What are chromosomes?

Answer 23

Chromosomes are structures made of DNA and proteins that carry genetic information. They are found in the nucleus of eukaryotic cells.

Question 23

How many chromosomes do humans have?

Answer 23

Humans have 46 chromosomes (23 pairs).

Question 24

What is the difference between a chromosome and a chromatid?

Answer 24

A chromosome consists of two chromatids connected by a centromere. Chromatids are identical copies of a chromosome formed during DNA replication.

Question 25

What does diploid mean?

Answer 25

Diploid cells have two sets of chromosomes (one set from each parent). Humans have diploid cells for most of their body cells (46 chromosomes).

Question 26

What does haploid mean?

Answer 26

Haploid cells have one set of chromosomes. Gametes (sperm and egg cells) are haploid, with 23 chromosomes in humans.

Question 27

Why is it important for gametes to be haploid?

Answer 27

Gametes need to be haploid so that when fertilization occurs, the resulting zygote has the correct diploid number of chromosomes.

Question 28

What does PMAT stand for in mitosis?

Answer 28

PMAT stands for Prophase, Metaphase, Anaphase, and Telophase, the four stages of mitosis.

Question 29

What happens during prophase?

Answer 29

During prophase, the chromosomes become visible, the nuclear envelope breaks down, and spindle fibers begin to form.

Question 30

What happens during metaphase?

Answer 30

During metaphase, chromosomes line up along the center (equator) of the cell.

Question 31

What happens during anaphase?

Answer 31

During anaphase, the sister chromatids are pulled apart to opposite sides of t

Question 32

What happens during telophase?

Answer 32

During telophase, the chromatids reach the poles, the nuclear envelope reforms, and the cell begins to divide.

Question 33

What is fertilisation?

Answer 33

Fertilisation is the fusion of a male gamete (sperm) and a female gamete (egg) to form a zygote.

Question 34

Why is fertilisation important?

Answer 34

Fertilisation restores the diploid number of chromosomes and creates genetic variation in offspring.

Question 35

Where does fertilisation occur in humans?

Answer 35

In humans, fertilisation usually occurs in the fallopian tubes.

Question 36

What is meiosis?

Answer 36

Meiosis is a type of cell division that reduces the chromosome number by half, producing four genetically diverse haploid gametes.

Question 37

How many divisions occur in meiosis?

Answer 37

Two divisions occur in meiosis: Meiosis I and Meiosis II.

Question 38

What is the result of meiosis?

Answer 38

The result of meiosis is four haploid cells, each with half the number of chromosomes of the original cell.

Question 39

How is genetic variation achieved in meiosis?

Answer 39

Genetic variation is achieved through processes such as crossing over (exchange of genetic material between homologous chromosomes) and independent assortment (random distribution of chromosomes).

Question 40

How is meiosis different from mitosis?

Answer 40

Mitosis results in two genetically identical diploid cells, while meiosis results in four genetically different haploid cells.