B12- reproduction 🧬

Question 1

RECAP: What are chromosomes?

Hint: carry genes

Answer 1

• Chrosomes carry the genes, that contain the instruction for making new cells, [aswell as all the tissues +organs required to make an entire new person/new you]
• body cells are paired + contain two of each chrosome.

Question 2

RECAP: What are genes ? [2]

Hint: small packet of information

Answer 2

• a gene, is a small packet of information that contains a characteristic, or part of a characteristic of your body.
• [It’s a section of your DNA and is carried in a large number, by chromosomes.]

Question 3

RECAP: What does the term ‘DNA’ mean?

Hint: makes up chromosomes

Answer 3

• DNA, is the unique molecule that makes up your chromosomes

Question 4

• RECAP- Fill in the gaps: Humans have __ chromosomes in the nuclues of your body’s cells, that are arranged in __ pairs.

Answer 4

• Humans have 46 chromosomes in the nuclues of your body’s cells, that are arranged in 23 pairs.

Question 5

What’s a gamete ?

Hint: an ordinary cell

Answer 5

• a gamete, is a sex cell which has half the chromosome number of an ordinary cell.
• in humans, the gametes are the sperm cell and the egg cell

Question 6

How many chromosomes do human sperm and egg cells, contain ?

Answer 6

• human sperm and egg cells, contain 23 single chromosomes.
• this is because, a gamete has half the chromosome number of an ordinary cell [as their chromosomes are not paired]

Question 7

How are gametes made ?

Answer 7

• gametes, are made by a type of cell division known as meiosis
• and unlike mitosis, meiosis produces non-indentical cells

Question 8

What is sexual reproduction ?

Hint: the fusion of…

Answer 8

• sexual reproduction, is the type of reproduction in which two parent organisms produce offspring, through the fusion of gametes, or sex cells.
• ; sexual reproduction, results in offspring with a unique combination of genetic material, from both parents.

Question 9

What is asexual reproduction ?

Answer 9

• asexual reproduction, is a form of reproduction that involves only one individual, with no fusing of gametes to produce the offspring

Question 10

What’s the difference between asexual reproduction 🆚 sexual reproduction ?

Answer 10

• asexual reproduction, is a form of reproduction that involves only one individual, with no fusing of gametes to produce the offspring
• sexual reproduction, is the type of reproduction in which two parent organisms produce offspring, through the fusion of gametes, or sex cells.
• ; sexual reproduction, results in offspring with a unique combination of genetic material, from both parents.

Question 11

What are the features of sexual reproduction ?

Answer 11

• sexual reproduction, involves the fusion [joining] of male and female gametes- this is known as fertilisation
• and in sexual reproduction, the offspring receives genetic information from both female and male parents
• variation can be seen in their offspring

Question 12

What is variation ?

Answer 12

• variation, is the differences in the characteristics of individuals, in a population

Question 13

In sexual reproduction, why can variation be seen ?

Answer 13

• in sexual reproduction, the offspring receives genetic information from both female and male parents
• ; because all gametes are different, this means variation can be seen in their offspring

Question 14

What are the features of asexual reproduction ?

Answer 14

• there is only one parent, so asexual reproduction doesn’t involve gametes
• in asexual reproduction, meiosis dosen’t take place- because gametes aren’t involved [it only involves mitosis]
• and in asexual reproduction, the offspring produced are genetically identical to the parent

Question 15

Why doesn’t asexual reproduction, involve gametes ?

Answer 15

• this is because there’s only parent therefore, there is no mixing of genetic information

Question 16

• Fill in the gaps: sexual reproduction can happen with only ____ parent, for example in flowering ______ that self-pollinate

Answer 16

• sexual reproduction can happen with only one parent, for example in flowering plants that self-pollinate

Question 17

What are some organisms that use asexual and sexual reproduction ?

Answer 17

• some organisms that use asexual and sexual reproduction are:
• dogs- use sexual reproduction
• aphids- use asexual reproduction

Question 18

What are the disadvantages and advantages, of sexual and asexual reproduction ?

Question 19

Compare and contrast asexual and sexual reproduction

Question 20

What’s another example, of organism that use asexual and sexual reproduction?

Answer 20

• sea turtles- use sexual reproduction
• yeast- uses asexual reproduction [as yeast cells divide by mitosis, to form a mass of identical cells]