S2. 6.3 Animal Nutrition

Question 0

Define ingestion

Answer 0

Taking substances into the body through the mouth

Question 1

What is meant by balance diet

Answer 1

Balance diet provides an adequate intake of the nutrients and energy needed to sustain the body and ensure good health and grow

Question 2

Define egestion

Answer 2

Passing out of food that has not been digested, as faeces, through the anus

Question 3

Function of mouth

Answer 3

Contains teeth used for mechanical digestion and is the area where food is mix with salivary amylase
It increases food surface area so it is easier for absorption later on,
Where ingestion take place

Question 4

Function of salivary gland

Answer 4

Produce saliva which contains amylase and helps to make food slide down the esophagus

Question 5

Oesophagus function

Answer 5

Tube shaped organ which uses peristalsis to transport food from the mouth to the stomach.

Question 6

Stomach function

Answer 6

Muscular wall squeeze on food to make it semi liquid. Contain pepsin to break down proteins into peptides
Kill bacteria with HCl

Question 7

Small intestine function

Answer 7

Final chemical digestion take place here

Nutrient from the food are absorbed here as well as transported throughout body in bloodstream

Question 8

Pancreas function

Answer 8

Produce pancreatic juice which contains amylase, trypsin, and lipase and hydrogencarbonate

Question 9

Liver function

Answer 9

Produce bile which is stored on the fall bladder

Question 10

Bile function

Answer 10

Contains salts that emulsify fats, forming droplets with a large surface area to make digestion by lipase more efficient

Question 11

Function of gall bladder

Answer 11

Store bile from liver

Question 12

Large intestine function

Answer 12

Tube shaped organ composed of colon and rectum

Question 13

Colon function

Answer 13

Absorption of some minerals and vitamins and reabsorbing water from waste to maintain the body’s water balance

Question 14

Rectum function

Answer 14

Where faeces are temporarily stored

Question 15

Anus function

Answer 15

A ring of muscle which controls when faeces is egestes from the body

Question 16

Define digestion

Answer 16

Break down of large insoluble food molecules into small, water-soluble molecules using mechanical and chemical processes

Question 17

Describe the incisor teeth

Answer 17

Front of the mouth

Chisel-shaped for biting and cutting

Question 18

Describe the canine teeth

Answer 18

Pointed for piercing and tearing

Question 19

Describe the premolars teeth

Answer 19

Uneven cups for grinding and chewing

Question 20

Describe the molars teeth

Answer 20

Like the premolars teeth but have 2-3

Use for chewing up the food

Question 21

Cause of dental decay

Answer 21

Sugar in the food stay trapped in between the teeth
Bacteria use the sugar to live
They produce a coating of plaque on the teeth
Bacteria produce acid which dissolves the enamels, forming a hole
Dentine underneath the enamel is softer -> dissolves more rapidly
If the hole reach the pulp cavity, bacterial infection can get to the nerve -> toothache and infection in the jaw (abscess)

Question 22

Describe the process of chewing

Answer 22

The chewing muscle contract and relax to move the lower jaw up and down
This makes the food between the teeth to be cut and crushed
The tongue help by moving food between teethe

Question 23

Describe peristalsis

Answer 23

It is the movement of food down the esophagus occur by a wave of muscular contraction
The circular muscle contract and the longitudinal muscle relax behind the food to push it along
In front of the food, the circular muscle relax and the longitudinal muscle contract to widen to oesophagus to allow the food to move along

Question 24

Describe the significant of chemical digestion

Answer 24

Enzymes are used to break down large insoluble substance into smaller, soluble molecule that can be absorbed

Question 25

Function, where it is release, substrate and end product of amylase

Answer 25

It is secreted from the salivary glands and pancreas, duodenum
It breaks down starch molecules into maltose

Question 26

Function, where it is release, substrate and end product of lipase

Answer 26

Pancreas, duodenum

Break down fat molecules into fatty acid and glycerol

Question 27

Function, where it is release, substrate and end product of protease

Answer 27

Stomach, duodenum, pancreas

Break down protein molecules into amino acid

Question 28

Define absorption

Answer 28

Movement of digested food molecules through the wall of the intestine into the blood or lymph

Question 29

What is the area of small intestine for

Answer 29

Region for absorption of digested food

Question 30

Which substances are small enough too pass through small intestine and into the blood?

Answer 30

Simple sugar, amino acid, fatty acid, and glycerol

Question 31

How is the small intestine adapted for absorption

Answer 31

Folded into many villi which increase surface area

Each villi is covered with cells which have even smaller projection on them, called microvilli

Question 32

Describe the structure of villi

Answer 32

Very thin wall, only 1 cell thick to enable molecules to pass through easily amino acids and sugar molecules are absorbed through the thin gillis wall into the blood capillary
Fatty acid and glycerol are absorbed into the lacteals
Hepatic portal vein transport absorbed food to the liver

Question 33

How much water do the small intestine and colon absorb every day?

Answer 33

Small intestine : 5-10 dm3

Colon : 0.3-0.5 dm3

Question 34

Define assimilation

Answer 34

Movement of digested food molecules into the cells of body where they are used, becoming part of the cells

Question 35

Describe the role of liver

Answer 35

Stores glucose by removing it from the blood and storing it as glycogen ( insoluble)
Helps to regular the concentration of glucose in the blood
Uses amino acids to make proteins, such as those included in blood clotting
Breaks down or destroyed excess amino acid
Site of breakdown of alcohol and other toxins
Convert fatty acid and glycerol into fat which is stored around the body

Question 36

Role of fat

Answer 36

Energy storage substance

Question 37

Define deamination

Answer 37

Removal of the nitrogen containing part of amino acids to form urea, followed by the release of energy from the remainder of amino acid

Question 38

Function of xylem and phloem

Answer 38

Plant tissues composed of cells that are specialized for transport
Xylem carries water and mineral throughout the plant and provides mechanical support for the plant (1 direction - from root via stem to leaves)
Phloem : carries sugar and other nutrients from the leaves to the cells for consumption or storage (2 directions)

Question 39

Describe the pathway taken by water through root

Answer 39

Water enters root hair cell by osmosis
As water enters the cell, it’s water potential becomes higher than in the cell next to it in the cortex
Water move by osmosis to the next cell
Water reaches the xylem
It is pulled up by the evaporation of water

Question 40

Define transpiration

Answer 40

Evaporation of water at the surfaces of the mesophyll cells followed by the loss of water vapor from plant leaves, through the stomata

Question 41

Describe the function of root hair cell

Answer 41

Absorb water and minerals from the soil
Have an elongated shape for more surface area
Anchor the plant into the soil

Question 42

Describe transpiration steam

Answer 42

Water is pulled up the xylem in the stem from the roots - leaves by transpiration all pull
The flow of water up the xylem relies on two properties of water
Cohesion and adhesion
-> there is a continuous flow of water from the roots to the leave

Question 43

Define water uptake

Answer 43

The process where transpiration produces tension, or a pull, from above creating a water potential gradient in the xylem, drawing cohesive water molecules up the plant

Question 44

Describe wilting

Answer 44

The amount of water lost from the leaves of a plant is more than the amount taken into the roots
So the plant will have a water shortage and cells become flaccid and are no longer turgid or full of water
Stems and leaves lose their rigidity and the stem is no longer upright and the leaves droop

Question 45

Define translocation

Answer 45

The movement of sucrose and amino acid in phloem

From region of production to region of storage or region of utilization in respiration or growth

Question 46

Describe systemic pesticides

Answer 46

The plant absorbs the pesticide
The pesticides are translocated to all parts of the plant in the phloem
Any insects or pests that eat enough plant tissue with the pesticide will die

Question 47

Argument for the addition of fluorine to public water supply

Answer 47

It helps teeth resist decay
Helps in healing by formation of new enamel
Cheap
Easy solution to help resist decay

Question 48

Argument against the addition of fluorine to public water supply

Answer 48

People should be given a choice

Negative long term effects

Question 49

Role of hepatic portal vein

Answer 49

Transport absorbed food to the liver

Question 50

Position of xylem and phloem in leaf, stem and root

Answer 50

Leaf: xylem ở trên, phloem ở dưới
Stem: xylem bên trong, phloem bên ngoài
Root: xylem liền nhau, phloem rời nhau