Science Final Flashcards
Describe the important nutrients that the body needs for growth and metabolism. What is the most important? Why?
1) Major nutrients are carbohydrates, fats, and proteins; vitamins and minerals are micronutrients; and water.
2) Water is the most important nutrient because the body’s vital processes (chemical reactions, breakdown of nutrients) take place in water.
What are the primary sources of energy (macromolecule) for the body? Give an example of each. Which one has the most energy per gram?
- Carbohydrates: fruits, sugarcane, sugar beets, honey, grains, and vegetables. 1 gram carbs = 4 calories.
- Fats: olive oil, butter, fat on meat 1 gram fat = 9 calories.
- Protein: eggs, meat, beans, and nuts. 1 gram protein = 4 calories.
- Fats have the most energy per gram.
Differentiate unsaturated and saturated fats. Give an example of each.
- Unsaturated fats (liquid at room temperature → olive oil)
- Saturated fats (solid at room temperature → butter, fat on meat).
What causes heartburn? What is the “cure”?
- Heartburn is a painful burning sensation in the chest caused by stomach acid backing up into the esophagus.
- Cure: not to over-eat, anti-acids, or prescription medicine if it is very serious.
Contrast chemical and mechanical digestion.
1) The mouth: Tongue and teeth to break down to ensure optimal absorption of nutrients. The saliva secreted contains enzymes that helps in softening the food into semi-solid lump.
2) The esophagus After food enters the esophagus, contractions of smooth muscle push the food toward the stomach No chemical digestion
3) The stomach Inside the stomach mechanical digestion called peristaltic contractions helps to churn the food bolus. Digestive juices and enzymes released by the stomach mix with the bolus to break down the food.
4) The small intestine Now the food is totally liquid and the small nutrients are absorbed by the body through millions of tiny fingers called villi. Juices from the pancreas and bile from the gallbladder enter the small intestine to breakdown food molecules even more.
5) The large intestine Water is absorbed into the blood stream. Food gets fermented by the gut bacteria.
Outline how digestion starts in the mouth and ends in the rectum. Be sure to list and explain the following and their functions: stomach, small intestine, liver, bile, pancreas, large intestine, rectum, hydrochloric acid, villi.
1) Mouth :Chewing begins, moisten food, carbohydrate digesting enzymes, mucus. 2) Esophagus Move food to stomach by peristaltic waves Mucus
3) Stomach Store, mix, dissolve, and continue digestion of food. Pepsin is the enzyme that breaks down protein and the mucus protects the stomach cells from the acid. Hydrochloric acid is to kill microbes and activate the enzyme pepsin. HCl, pepsin, mucus
4) Pancreas Secretion of enzymes and bicarbonate into the small intestine. Enzymes to digest carbs, fats, an proteins. Bicarbonate to neutralize acid. Enzymes and bicarbonate
5) Liver Secretion of bile salts into the gallbladder. Bile salts → solubilize water-insoluble fats.
6) Small intestine Food digestion. Absorption of nutrients through the villi. Enzymes, mucus, salt and water
7) Large intestine Absorption of salt and water.
8) Rectum Storage and concentration of undigested matter.
Why does your mom say not to swim or run after just eating?
Because your digestive system is working and most of your energy is needed to digest or process the food you just ate. Also a lot of your blood supply is going to your digestive system to carry the nutrients and energy necessary for your body and later activities like swimming and running.
- Describe what a healthy diet should be like.
- 6-11 servings of bread, cereal, rice and pasta group
- 3-5 servings of vegetables and 2-4 servings of Fruit
- 2-3 servings of milk, yogurt, and cheese group
- 2-3 Servings of meat, poultry, fish, beans, eggs, nuts group
- Fats, oils and sweets use sparingly
Outline how blood flows starting at the right atrium and ending at the left atrium.
What are the functions of the cardiovascular system? What is the function and structure of the heart?
a) The cardiovascular system carries needed substances to cells and carries waste products away from cells. In addition, blood contains cells that fight disease.
b) Each time the heart beats it pushes blood through the body vessels of the cardiovascular system. The heart is about the size of your fist and located in the center of your chest.
c) The heart has a right and a left side and they are completely separated from each other by a wall of tissue called the septum. Each side has 2 compartments: the lower chamber (ventricle) and the upper chamber (atrium).
What are the functions and structures of the arteries, capillaries, and veins? What are the components of blood?
- a) Arteries: the walls of arteries are generally very thick and consist of 3 cell layers. They carry blood away the heart.
- b) Capillaries: in the capillaries materials are exchanged between the blood and the body cells. Capillary walls are only on cell thick.
- c) Veins: carry blood back to the heart. The walls of veins have 3 layers with muscle in the middle layer.
Why are the coronary arteries important?
Because they supply blood to the heart which in turn provide oxygen and nutrients to the heart to keep it functioning.
What determines the type of blood that a person can receive in a transfusion? What are the structures and functions of the lymphatic system?
a) The marker molecules on your red blood cells (A, B, AB, and O) determine your blood type and type of blood that you can safely receive in transfusion.
b) The lymphatic system is a network of vein-like vessels that return fluids to the blood stream.
- What are some diseases of the cardiovascular system? What behaviors can help maintain cardiovascular health?
a) Arteriosclerosis, Hypertension, heart attack.
b) Healthy eating and exercise.
Your friend eats a lot of fatty foods and does not exercise. However, he looks perfectly fine. You know better. Explain to him what’s happening inside of him.
His veins are getting clotted with build up of fatty material this in turn makes the heart work harder and eventually he will get hypertension or and arteriosclerosis. So he needs to exercise to make his heart more efficient and change his eating habits to clean his arteries and veins.
Why can’t a person hold his breath for a long period of time?
Because your lungs aren’t getting enough oxygen rich air and the carbon dioxide accumulates sending a signal to the brain to breathe again.
What is a heart attack? What can you do to prevent it?
a) Occurs when blood flood to part of the hear muscle is block in other words when the coronary arteries or veins are blocked.
b) Preventing atherosclerosis by not eating a fatty diet and by exercising.
What are the functions of the respiratory system? What structures does air pass through as it travels to the lungs?
a. Moves oxygen from outside of the environment into the body. It also removes carbon dioxide and water from the body. b. Nose, pharynx, trachea, bronchi and lungs
What happens during gas exchange and breathing? Why is high surface area important in gas exchange?
- After air enter the alveolus, oxygen passes through the wall of the alveolus and then through the capillary wall into the blood. CO2 and H2O pass from the blood into the alveolus.
- High surface area is important because enables the lungs to absorb a large amount of O2.
Explain the process of breathing as the body uses negative breathing pressure. Exhaling requires no energy why?
- When you breathe the action of your rib muscles and diaphragm expand or contract in your chest.
As a result airs flows in or out. - When Exhaling your rib muscles and diaphragm relax.
What harmful chemicals are found in tobacco smoke?
Tart, carbon monoxide, and nicotine.
How the kidneys filter waste from blood? How does excretion contribute to homeostasis?
- The nephrons filter waste in stages. First both waste and needed materials are filtered out of the blood, then much of the needed material is returned to the blood, and waste is eliminated from the body.
- By keeping the body’s internal environment stable and free of harmful levels of chemicals.
What happens to the filtration process when you drink too much water? Drink too little water?
Too much water the urine is very diluted because there is little reabsorption of water in the nephrons
Too little water the urine is very concentrated because there is a lot of reabsorption of water in the nephrons
Water and oxygen allow for life no other planet in the solar system has those elements. What does say about our Creator and our Earth?
He is a good God and that every living thing depends on those basic elements Water and oxygen.
Describe the structure of a neuron. Give TWO examples of a neuron and their functions.
- sensory neurons receive information from the sensory receptors,
- interneurons transfer and interpret impulses, and
- motor neurons send appropriate impulses/instructions to the muscles and glands.
What happens at the synapse? Why do drugs cause havoc on the synaptic cleft?
- When a nerve impulse reaches the synapse at the end of a neuron, it triggers the neuron to release a chemical neurotransmitter into a cleft and then the receptors of another neuron picks up the chemical.
- Drugs over-stimulate or under-stimulate the release of neurotransmitters in the synapse.
What are the levels of organization within an ecosystem?
- ecosystem
- community
- Population
- and the smallest is a single organism
