Animal physiology (B9) without respiration system and circulatory system

Question 1

what is respiration?

Answer 1

chemical process which occurs in cells to release energy

Question 2

What is aerobic respiration and how is it different to anaerobic respiration?

Answer 2

respiration using oxygen producing energy in the form of ATP. This form of respiration is more efficient and releases more energy than anaerobic respiration.

Question 3

where does aerobic respiration occur in eukaryotes and prokaryotes?

Answer 3

-In eukaryotes, it occurs inside the mitochondria
-In prokaryotes it occurs in the cytoplasm

Question 4

what is the word equation for aerobic respiration?

Answer 4

glucose + oxygen -> carbon dioxide + water + energy (ATP)

Question 5

What anaerobic respiration?

Answer 5

respiration without oxygen. It releases less energy but it is important for cells that cannot obtain sufficient oxygen.

Question 6

what is the word equation for anaerobic respiration?

Answer 6

glucose-> lactic acid (toxic molecule) + energy (ATP)

Question 7

what occurs when we exercise?

Answer 7

-energy is needed for muscle contraction
-breathing rate and heart beat will increase allowing more oxygen and glucose to reach muscle cells
-body may break down glycogen stores to release more glucose
-anaerobic respiration will occur when there isn’t enough oxygen
-after exercise, breathing rate will remain high to replenish oxygen debt and remove toxic lactic acid

Question 8

what is the nervous system?

Answer 8

rapid communication system by sending electrical impulses producing quick but short-lived response.

Question 9

what is the central nervous system?

Answer 9

It consists of the brain and spinal cord. Nerves from receptors of sense organs brings Impulses to the spinal cord and send them to the brain for processing. The brain interprets and responds by sending an impulse via spinal cord to the nerves which connect to the organs and tissues.

Question 10

what is the spinal cord?

Answer 10

a collection of nerves that run down the spine through the vertebrae.

Question 11

what is a neurone?

Answer 11

a nerve cell is a neurone. They transmit electrical impulses. They can extend their cytoplasm to allow travel of electrical impulses.

Question 12

What are the three types of neurone?

Answer 12

sensory, relay and motor

Question 13

the function of sensory neurones?

Answer 13

connects receptors, which detect stimuli in the environment with the central nervous system

Question 14

function of the relay neurone?

Answer 14

found within the central nervous system. These connect the sensory as well as motor neurones and allow communication to and from the brain

Question 15

function of motor neurone?

Answer 15

connects central nervous system to effectors. Effectors include muscles and glands which produce a response to the electrical impulse.

Question 16

Describe the structure of a neurone

Answer 16

long section the electrical impulse can travel through is called the axon. This is protected by myelin sheath which allows impulse to travel faster. Dendrites allow them to make connections with other neurones

Question 17

what is a synapse?

Answer 17

a small gap between two neurones. They allow neurones to transmit electrical impulses to each other. Connections are made between dendrites.

Question 18

How does an impulses cross a synapse?

Answer 18

when the impulse reaches the end of a neurone, a neurotransmitter chemical is released. This diffuses across the synapse. When it reaches the surface of the dendrite, it binds to a receptor and an electrical impulse regenerates which travels down the other neurone.

Question 19

what is the reflex arc used for?

Answer 19

for a quick reflex action, designed to protect the body from harm. They do not require processing from the brain.

Question 20

Describe the process of the reflex arc?

Answer 20

-receptor detects stimuli
-receptor generates electrical impulse
-electrical impulse passes down form sensory neurone to spinal cord
-impulse travels to relay neurone using chemical transmitters
-electrical impulses connects to motor neurone to the effector
-the effector is a muscle which will contract

Question 21

where is the respiration system found?

Answer 21

in the thorax (chest)

Question 22

what is the digestive system involved in?

Answer 22

-breakdown of large insoluble molecules into their soluble products
-the absorption of these products in digestion

Question 23

in what order does food pass through the digestive system?

Answer 23

-mouth
-oesophagus
-stomach
-small intestine
-large intestine

Question 24

how is food moved in the digestive system?

Answer 24

by peristalsis, waves of muscular contraction that move bolus(ball of food)

Question 25

what are the two stages of digestion?

Answer 25

-mechanical: teeth grinding, stomach churning
-chemical: using bile and enzymes

Question 26

function of hydrochloric acid in the stomach?

Answer 26

kill bacteria and provide correct pH for the protease enzyme to digest protein

Question 27

function of bile and pancreatic juice?

Answer 27

they contain hydrogen carbonate (bicarbonate) ions to neutralise stomach acid when entering the small intestine and provide alkaline conditions needed by enzymes.

Question 28

Function of bile?

Answer 28

made in the liver and stored in gall bladder. It is released into small intestine and emulsifies lipids to increase surface area for lipase to work and increase the rate of digestion.

Question 29

what happens to glucose and amino acids once digested?

Answer 29

pass through gut and absorbed into the blood

Question 30

what happens to glycerol and fatty acids once digested?

Answer 30

pass through gut into lymph system before entering the blood

Question 31

Describe the structure of the small intestine

Answer 31

-contains villi which increases surface area
-contains many blood capillaries for good blood supply. Blood flow maintains steep concentration gradient.

Question 32

how are nutrients absorbed?

Answer 32

diffusion and active transport. Active transport makes sure no digested food is wasted.

Question 33

how do enzymes break down molecules?

Answer 33

through hydrolysis

Question 34

how do enzymes make macromolecules?

Answer 34

through condensation reactions.

Question 35

how is energy stored?

Answer 35

-excess glucose converted into glycogen and stored in the liver and muscle cells
-fatty acids are a concentrated energy store

Question 36

what happens to undigested food?

Answer 36

all digested products should be absorbed in the small intestine. Indigestible food such as cellulose (fibre) is passed on into the large intestine. Bile pigments cause the brown colour of faeces. This passes into the rectum and egested through anus

Question 37

what is excretion?

Answer 37

removal from organisms of toxic material and substances in excess

Question 38

Since the body can’t store proteins or amino acids, what happens to the excess?

Answer 38

excess amino acids are broken down by the liver through deamination. The nitrogen component is converted to urea which can be toxic if the blood level is too high so urea is excreted through kidneys.

Question 39

how does the liver break down Haemoglobin?

Answer 39

product is a yellow/green bile called bilirubin which is excreted with bile. This is expelled with faeces.

Question 40

Is sweating from the skin considered to be an excretory process?

Answer 40

It could be as sweaty consists of sodium chloride and traces of urea but it is not a response to changes in blood composition

Question 41

what are the kidneys three main roles in filtering the blood?

Answer 41

-removal of urea
-adjustment of ion content
-adjustment of water content

Question 42

how do kidneys filter the blood?

Answer 42

-each kidney receives blood from the aorta via the renal artery
-blood is filtered to remove urea, excess water and salts
-filtered blood returns to vena cava via renal vein.
-the mixture of substances removed from blood plasma is called urine. It is passed down a ureter to bladder there it is stored
-A sphincter muscle at the base of the bladder controls the release of urine through the urethra.

Question 43

what microscopic structures is the process of ultrafiltration associated with and describe their structure?

Answer 43

nephrons which consists of glomerulus, renal capsule and renal tubule. Capillaries leaving the glomerulus are closely associated with the tubule.

Question 44

what three main regions is the kidney composed of?

Answer 44

cortex, medulla and pelvis

Question 45

how does blood travel through the three regions?

Answer 45

-blood enters kidneys through renal artery
-each capillary becomes knotted to form glomerulus which is surrounded by bowman’s capsule
-This leads to a convoluted tubule. The proximal convoluted tubule passes down into the medulla, where it forms the loop of Henle, returning to a distal convoluted tubule in the cortex again.
-The tubule joins a collecting duct, which passes down through the medulla into the pelvis of the kidney.

Question 46

How does the nephron function to when the filtrate passes to the renal tubule?

Answer 46

-The wall of the capillary of the glomerulus acts as a filter. As the blood enters the glomerulus, its pressure increases.
-Large structures (blood cells) and large molecules, e.g. plasma proteins, are retained within the capillary, but smaller molecules (water, dissolved salts (ions), glucose and urea) are forced out by ultrafiltration. This is filtration under pressure.
-The filtrate is collected by the renal capsule and passes into the renal tubule.

Question 47

How does the nephron function to after the filtrate passes to the renal tubule?

Answer 47

-As the filtrate passes along the tubule, selective reabsorption takes place into the capillaries surrounding the tubule.
-Glucose is reabsorbed by diffusion and active transport.
-Water is reabsorbed by osmosis, along with some salts by diffusion and active transport to maintain the correct concentration in the blood.

Question 48

what happens to the salt along with urea and uric acid not needed in the body?

Answer 48

they continue along the tubule into a collecting duct in the medulla.

Question 49

what occurs at the collecting duct?

Answer 49

delivers the filtrate to the pelvis of the kidney, where the fluid (urine) passes into a ureter to transfer it to the bladder for storage.

Question 50

how is urine expelled?

Answer 50

Urine is retained in the bladder by a sphincter muscle at its base. When the sphincter muscle relaxes, the muscle wall of the bladder contracts to expel the urine (a process called urination) through the urethra.

Question 51

what is homeostasis?

Answer 51

the maintenance of a constant internal environment

Question 52

what is the role of kidneys in homeostasis?

Answer 52

-can remove chemicals which might poison enzymes (pH changes)
-controls levels of salts (ion), acids and water in the blood

Question 53

how does the kidney respond to water loss through sweating?

Answer 53

By producing a smaller volume of more concentrated urine to conserve water in the body. Without this, the body may dehydrate.

Question 54

how does the kidneys respond when less water is lost through sweating?

Answer 54

Kidneys respond by producing a larger volume of less concentrated urine. Without this, the body may over hydrate causing cells to burst.

Question 55

what hormone controls how much water is excreted by the kidneys?

Answer 55

ADH