Science 8 - Exam Reviewer

What is the digestive system made up of?

gastrointestinal tract and accessory organs

What is the digestive system mainly responsible for?

digestion and absorption of food

What organ serves as the entry point for food?

mouth

What is the digestive enzyme found in saliva?

ptyalin/salivary amylase

What is the function of ptyalin?

digests starch and breaks it down into maltose and dextrin

three major human salivary glands

parotid, sublingual, submandibular

another term for pharynx

throat

In what organ does food turn into bolus?

pharynx

What is the function of the epiglottis?

closes windpipe upon swallowing the food

What muscular tube connects the mouth to the stomach?

esophagus

How does food (bolus) move through the esophagus?

peristalsis

What is the purpose of esophageal sphincters?

allow food to enter the stomach, stop food from going back up into the esophagus

What is the stomach?

a muscular sac that stores and digests food

What does gastric juice contain?

hydrochloric acid and pepsin

In what organ does bolus turn into chyme?

stomach

What are the dimensions of the small intestine?

about 6-7m long, 2-4cm wide

In what organ does the absorption of nutrients and minerals from the food take place?

small intestine

What are the three segments of the small intestine?

duodenum, jejunum, ileum

What is the function of the duodenum?

for the digestion and neutralization of the chyme’s activity

What is the function of the jejunum?

absorbs sugars, amino acids, and fatty acids

What is the function of the ileum?

absorbs vitamin B12, bile salts, and other nutrients not absorbed by jejunum

What is the function of the liver?

secretes bile to emulsify fats in the small intestine

What is the function of the gallbladder?

stores bile

What is the function of the pancreas?

breaks down protein, fats, and carbohydrates

What is the other term for large intestine?

colon

What is the function of the large intestine?

responsible for the reabsorption of water and mineral salts

Where is the appendix located?

attached to the large intestine, lower right abdomen

What is the function of the rectum?

temporarily stores the undigested food from the colon, which becomes stool or feces

What organ marks the end of the gastrointestinal tract?

anus

What is the correct order of the five digestive processes?

ingestion, digestion, absorption, assimilation, elimination/excretion

In what organ does ingestion begin?

mouth

What happens during ingestion?

mastication/chewing

What is the process of digestion?

ingested food is broken down into simplest forms that can be absorbed and assimilated into the tissues of the body

What are the two types of digestion?

mechanical and chemical

What is absorption?

release of digested food into the bloodstream

In what organ of the body does absorption start?

stomach

In what organ of the body does most of the absorption process happen?

small intestine, jejunum and ileum

What is assimilation?

nutrients are taken from the blood and into the cells

What is elimination/excretion?

removal of metabolic waste products from the body in the form of stool or urine

What are the four main macronutrients?

carbohydrates, protein, fats and oils, water

Ketosis happens when the body is low on…

carbohydrates

What happens during ketosis?

The body transforms fat into acids which it uses for energy.

What does ketosis result in?

weight loss but dehydrated

What are the three main types of carbohydrates?

monosaccharides, disaccharides, polysaccharides

What are monosaccharides?

simple sugar units (glucose, fructose, galactose)

What are examples of foods that contain monosaccharides?

fruits, honey, candy, corn syrup

What are disaccharides?

composed of two monosaccharides fused together

What are examples of foods that contain disaccharides?

dairy, bread, sweet potato

What are polysaccharides?

composed of more than 10 monosaccharides

What are polysaccharides otherwise known as?

fiber

What are the two types of fiber?

soluble and insoluble

What does protein do for the body?

mainly used for growth and repair, but can also be used as energy when there are no carbohydrates

What is protein made up of?

amino acids

What are examples of foods that contain protein?

meat, eggs, nuts, soy

What do fats and oils do for the body?

provide energy, synthesize hormones and other substances needed for the body’s activities

What are the two types of fats?

saturated and unsaturated

What are saturated fats?

unhealthy fats, too much can lead to heart and blood vessel problems

What are unsaturated fats?

healthy fats, occur as liquid under room temperature

How much of the human body is composed of water?

around 70%

What does water do for the human body?

flushing out toxins, transporting nutrients, preventing constipation, and lubricating and hydrating the body organs

What are the two main types of micronutrients?

vitamins and minerals

What are vitamins?

organic molecules found in food in small amounts

What are the two types of vitamins?

fat-soluble, water-soluble

What are the four types of fat-soluble vitamins?

Vitamin A, D, E, and K

What does Vitamin A do for the body?

better eyesight, skin, and hair

What does Vitamin D do for the body?

healthier bones

What does Vitamin E do for the body?

supports muscles and nervous system

What does Vitamin K do for the body?

helps in blood clotting

What are the two types of water-soluble vitamins?

Vitamin B and C

What does Vitamin B do for the body?

helps in processing the nutrients in food for energy and growth

What does Vitamin C do for the body?

holds cells together and assists in healing wounds

What do minerals do for the human body?

inorganic substances that ensure a person’s health, makes sure that a person’s soft tissues, fluids and skeletal system are working properly

What do calcium, phosphorus, and fluorine do for the body?

healthy teeth and bones

What do sodium, potassium, and chlorine do for the body?

proper fluid balance

What does iodine do for the body?

regulates growth and development of the body

What does zinc do for the body?

aids in healing wounds

What is malnutrition?

lack of proper nutrition, caused by not having enough to eat, not eating enough of the right things, or being unable to use the food that one eats

What are the four major deficiency disorders among Filipino children?

Protein-energy malnutrition (PEM), Vitamin A Deficiency (VAD), Iron Deficiency Anaemia (IDA), Iodine Deficiency Disorder (IDD)

a common childhood disorder primarily caused by deficiency of energy, protein, and micronutrients

Protein-energy malnutrition (PEM)

a severe form of malnutrition that happens when a person does not get enough proteins

Kwashiorkor

a severe form of malnutrition that happens when a person does not get enough proteins and calories

Marasmus

• associated with significant morbidity and mortality from common childhood infections

• the world's leading preventable cause of childhood blindness

Vitamin A Deficiency

occurs when there are not enough healthy red blood cells (hemoglobin) to carry oxygen to your body's organs

Iron Deficiency Anemia (IDA)

What are somatic cells?

body cells

What are gametes?

sex cells

What are the four phases of interphase?

G1 (primary growth), S (synthesis), G2 (secondary growth), G0 (permanent/temporary rest)

What are the two important stages of the cell cycle?

interphase, cell division

What are the two types of cell division?

mitosis and meiosis

Where does DNA replication occur?

interphase

What must occur before mitosis?

DNA replication

Identify the phase of mitosis.

“nucleolus disappears“

prophase

Identify the phase of mitosis.

“nuclear envelope disappears“

prophase

Identify the phase of mitosis.

“chromatin condenses to chromosomes“

prophase

Identify the phase of mitosis.

“duplicated chromosomes appear as sister chromatids“

prophase

Identify the phase of mitosis.

“spindle fiber begins to form”

prophase

Identify the phase of mitosis.

“centrioles move away from each other”

prophase

Identify the phase of mitosis.

“centrioles are on the opposite poles of the cell”

metaphase

Identify the phase of mitosis.

“chromosomes line up at the metaphase plate”

metaphase

Identify the phase of mitosis.

“centromeres of all chromosomes are aligned with each other”

metaphase

Identify the phase of mitosis.

“sister chromatids are aligned to one another”

metaphase