Human Nutrition

Her energy needs decrease

Her energy needs stay exactly the same

Her energy needs increase to support the fetus

She only needs more vitamins, not more energy

It causes scurvy

It leads to brittle bones

It can block the coronary arteries

It causes a lack of energy

Dried apricots

Cucumber

Peanut butter

Bread

Vitamin A

Vitamin B

Vitamin C

Vitamin D

Proteins

Vitamins

Carbohydrates

Fats

Acting as a primary enzyme for digestion

Providing thermal insulation under the skin

Transporting oxygen in the blood plasma

Binding to DNA to regulate gene expression

Vitamin A

Vitamin B1

Vitamin C

Vitamin D

They are necessary for the formation of a blood clot by activating prothrombin

They are required for the transport of carbon dioxide as bicarbonate ions

They act as the main source of energy for the contraction of smooth muscles

They prevent the oxidation of Vitamin C in the plasma

Blood pH increases (alkalosis) due to the accumulation of urea

Blood pH decreases (acidosis) due to the production of ketone bodies from fat breakdown

Blood pH remains perfectly constant due to the buffering capacity of hemoglobin

Blood pH decreases due to the increased concentration of dissolved oxygen

It has a high latent heat of vaporization, allowing significant heat loss through sweating

It is a product of aerobic respiration and provides energy for cooling the body

It acts as a lubricant for the movement of joints during exercise

It transports glucose to the skin where it is oxidized to release heat

Oesophagus

Bile duct

Ureter

Pancreatic duct

Enamel

Dentin

Pulp cavity

Cement

To increase the surface area for enzyme action

To decrease the temperature of the food

To turn proteins into starch

To prevent water from being absorbed

Stomach

Small intestine

Colon

Liver

The gut lumen widens

The gut lumen narrows and pushes food forward

The gut shortens in length

Food is moved backward toward the mouth

Production of bile

Storage of glycogen

Production of digestive enzymes like trypsin

Deamination of excess amino acids

Because cellulose is toxic to human cells

Because humans lack the enzyme cellulase

Because fiber moves too slowly through the gut

Because fiber is absorbed in the stomach

To slow down the movement of food to allow more time for digestion

To provide a large surface area for the efficient absorption of nutrients

To secrete large amounts of digestive enzymes into the lumen

To protect the delicate lining of the intestine from acidic chyme

Starch is broken down into glucose by amylase in one step

Starch is broken down into maltose by amylase, then maltose into glucose by maltase

Starch is emulsified by bile then broken down by lipase

Starch is converted into amino acids by protease in the stomach

Nutrients are used by the body's cells to build new molecules

Undigested food material is passed out of the body through the anus

Waste products of metabolism are removed from the blood by the kidneys

Soluble food molecules are moved from the gut into the blood

Esophagus

Stomach

Small intestine

Large intestine

Producing enzymes

Producing bile

Storing and concentrating bile

Storing feces

To physically crush food

To speed up the breakdown of large molecules

To change the color of food

To move food through the intestines

$Starch \rightarrow Maltose$

$Protein \rightarrow Amino acids$

$Fats \rightarrow Glycerol$

$Maltose \rightarrow Glucose$

By breaking chemical bonds in the lipid molecules

By providing an acidic environment for lipase

By emulsifying fats to increase the surface area for lipase to act on

By acting as a co-enzyme for lipase

Hardening of the enamel

Formation of a hole in the enamel and dentine

Increase in saliva production

Strengthening of the jawbone

Rectum

Anus

Colon

Ileum

It has a much thicker muscular wall for more intense mechanical breakdown.

It is longer and contains many membrane-bound enzymes on its microvilli.

The $pH$ is much lower, allowing for the activation of different types of proteases.

It is the only part of the small intestine that receives secretions from the liver.

The chewing (mastication) of food by teeth.

The emulsification of fats by bile salts.

The churning of food by the muscular walls of the stomach.

The hydrolysis of starch into maltose by amylase.

They are not digested and are excreted as waste.

They are broken down by nucleases produced by the pancreas and small intestine.

They are hydrolyzed by the high acidity of the stomach without the need for enzymes.

They are converted into proteins by the bacteria in the large intestine.

Small intestine

Liver

Heart

Kidney

Nitrogen gas

Ammonia

Urea

Nitrate

Nutrients enter the blood

Undigested food is removed from the body

Enzymes break down proteins

Glucose is stored as glycogen

Nucleus

Ribosome

Mitochondrion

Vacuole

In the hepatic portal vein

In the lacteals and lymphatic system

In the red blood cells

In the renal artery

Constipation

Diarrhea

Scurvy

Anemia

Absorption is chemical, assimilation is physical

Absorption is taking in nutrients; assimilation is using them in cells

Assimilation happens in the gut; absorption happens in the liver

There is no difference; they are the same process

Microvilli $\rightarrow$ Epithelial cell $\rightarrow$ Capillary wall

Lacteal $\rightarrow$ Epithelial cell $\rightarrow$ Microvilli

Capillary wall $\rightarrow$ Microvilli $\rightarrow$ Epithelial cell

Epithelial cell $\rightarrow$ Lacteal $\rightarrow$ Capillary wall

Glucagon

Adrenaline

Insulin

Thyroxine

The long length of the small intestine.

The presence of circular folds and villi.

The acidic pH of the ileum contents.

The thinness of the epithelial layer.