Unit 3 Digestion, Respiration with types. Done

Question 1

Metabolism

Answer 1

Chemical reactions in the body.
2 types:
Catabolism: The process by which larger molecules are broken down into smaller ones.
eg: Digestion.

Anabolism: The process of building up more complex molecules using smaller ones.
eg: Bone development, mass gain.

Question 2

Nutrition with types (no need in the exam)

Answer 2

The process of obtaining and using the food needed for health and growth. Nutrients are the materials that provide nutrition.

Nutrition has 2 types:
Autotrophic:
Preparing own food which is the main source of energy for producers. eg: Photosynthesis used by plants to convert solar energy into chemical energy and carbohydrates are formed.

Heterotrophic:
Gaining energy from other organisms.

Has 3 types:
Saprophytic nutrition: Secretes digestive juices out of the body and then absorbs the digested food. eg: Decomposers, House flies.

Parasitic nutrition: Lives inside another organism and takes nutrition from it. eg: parasites.

Holozoic nutrition:
The organism eats the other organism and digests it in the body.
Steps:
1)Ingestion: Taking the food in.
2)Digestion: Breaking complex food molecules into simpler ones that can be used by the body.
3) Absorption: Absorbing digested food.
4) Assimilation: Using digested food.
5)Egestion: Removing undigested food from the body.
eg: most animals

Question 3

Human Digestion: The process and the parts

Answer 3

check image: Salivary glands

Consists of 2 parts:
Alimentary Canal: It comprises of mouth, esophagus, stomach, small intestine, and large intestine.

Associated Glands: The main associated glands are
◦ Salivary gland: order from the closest to the chin: sublingual gland, submandibular gland, parotid gland.
#check image.
◦ Gastric Glands
◦ Liver
◦ Pancreas

Process: Food enters the mouth where you break down food using your teeth, turn them using your tongue and salivary glands produce saliva which helps in turning starch into maltose.

The food is swallowed and goes to esophagus which takes it to the stomach with a wavy movement pushing the food down called peristalsis.

The food gets to the stomach which is a highly muscular bag-like organ that produces HCl, enzyme gastric lipase, and enzyme pepsin. Lipase digests fats, and HCl kills germs and creates an acidic environment for pepsin to digest proteins.

The food then goes to the small intestine which is a long tube that helps in digesting food, it has villi on its walls to help in absorbing nutrients. It gets bile from the gall bladder (liver (largest human organ) produces, gall bladder store) which helps in the mechanical digestion of fats.
It gets pancreatic lipase which digests fats into fatty acids and glycerol and pancreatic trypsin which digests proteins into peptones from the pancreas.

undigested food then goes to the large intestine where water and some salts are absorbed.
The remaining materials are stored in the rectum and removed by the anus.

Question 4

Types and steps of Cellular respiration

Answer 4

Anaerobic respiration: Without O2 occurs in cytoplasm.
2 types
ALcoholic fermentation: no need for now
lactic acid fermentation:
Glucose → 2 Lactic Acid + Energy

When we run we need more energy and only aerobic respiration isn’t enough so we use anaerobic respiration, specifically lactic acid fermentation. When lactic acid is produced into the muscle this causes pain and taking some rest would help.

Aerobic respiration: With O2 occurs in mitochondria.
C6H12O6 + 6O2 → 6CO2 + 6H2O Glucose + oxygen → carbon dioxide + water

Aerobic Respiration in Humans:
Air enters the nose and is filtered and warmed in the nasal cavity with hair and mucus.
Air moves to the pharynx and then to the sound body (larynx) then into the trachea which is a long tube that has semi-circular cartilage rings that help the trachea to stay open.
The trachea is then separated into 2 similar parts called bronchi. bronchi is further split into bronchioles. bronchioles end have alveoli which is a cloud-like structure with thin walls that allow diffusion to happen and provide a large surface area for diffusion to happen efficiently. O2 goes to the bloodstream due to diffusion and CO2 goes to the alveoli due to diffusion.

Inhalation: The chest expands and the diaphragm contracts providing more volume and lowering the pressure also vacuuming the air into the lungs.

Exhalation: After the gas exchange happens the chest returns to its form and the diaphragm relaxes pushing the air with CO2 out of the body.

Question 5

Effects of Growing Up on Digestion and Respiration

Answer 5

Digestion efficiency tends to get lower as we grow up because:
1) Slower Metabolism.
2) Decreased Production of Digestive Enzymes.
3) Reduced Stomach Acid
4) Decreased Physical Activity

Respiration efficiency tends to get lower as we grow up because:
1) Weaker Respiratory Muscle Strength.
2)Decreased Vital Capacity (maximum amount of air a person can exhale after a maximum inhalation)

Question 6

Cigarette effect on lunges and how to improve the rate of respiration

Answer 6

Cigarette smoking has a huge and terrible effect on lung health and respiratory function:

1) Damages lung tissues.
2) Accelerated aging of the lungs.
3) Increased risk of respiratory infections.

Strategies to improve respiration rate:

1) Most important(Quitting smoking if you do smoke)
2) Regular exercises
3) Breathing exercise and cardio
4) Avoiding environmental pollutants.
5)Regular medical checkups.