reproductive male

Question 1

define spermatogenesis

Answer 1

the formation of sperm in the testes

Question 2

define point 1

Answer 2

occurs inside the seminiferous tubules that are in each testis. These tubes are lined with immature cells called spermatogonia.

-these cells are diploid, they lie dormant until puberty
-at puberty the cells begin to divide by mitosis and provide a continuous source of new cell for sperm production

Question 3

define point 2

Answer 3

some of the diploid daughter cells get pushed inwards towards the centre of the tubule, where they undergo a period of growth. these enlarged calls are then called Primary Spermatocytes. (Diploid)

Question 4

define point 3

Answer 4

Primary Spermatocytes undergo the first stage of meiosis to produce Secondary Spermatocytes (haploid). After the second stage of meiosis these divid into Spermatids.

Question 5

define point 4

Answer 5

hence, one diploid spermatogonium forms four haploid spermatid

Question 6

describe the final stage of spermatogenesis

Answer 6

the final stage is when spermatids mature into sperm

-much of cytoplasm is lost
-A tail is formed
- during maturation, the sperm is nourished by other special cells

Question 7

state why humans need food

Answer 7

food (nutrients)= any substance required by the body for a healthy functioning

food/nutrients are required:
to produce energy for cell activities
to regulate body processes
as materials to build new cells

Question 8

name the 6 classes of nutrients

Answer 8

carbohydrates, minerals, water, protein, fats, vitamins

Question 9

state the basic units of carbohydrates, fats and proteins

Answer 9

simple sugars
fatty acids
amino acids

Question 10

why do we need a digestive system?

Answer 10

we need the 6 classes of nutrients to function correctly.

vitamins, minerals and water are small and can easily pass into cells

BUT simple sugars, amino acids and fatty acids come from complex carbohydrates, proteins and fats. These larger molecules need to be broken down into smaller units before they can be absorbed into the cells.

it is the process of breaking down these nutrients to enable the smaller molecules to be absorbed into the blood.
-that is the primary purpose of the digestive system

Question 11

define Alimentary canal

Answer 11

A continuous tube that runs from your mouth to anus.

the lining of the alimentary canal is the surface through which nutrients are absorbed.

it has 6 major functions.

Question 12

state the six functions of the digestive system

Answer 12

1. ingestion of food and water
2. mechanical digestion of food
3. chemical digestion of food
4. movement of food along alimentary canal
5. absorption of digested food and water into the blood and lymph
6. elimination of material that is not absorbed