Biology Final Exam (all information after midterm 2)

Homeostasis

process by which organisms maintain a relatively stable internal environment

Diffusion

the process in which organisms gain and lose water

Active Transport

the movement of materials through a cell membrane using energy

Percentage of water in humans

60%

How much water can a cell lose before it becomes deadly?

12%

Tempature organisms must maintain

between 0 and 40 degrees celsius

What happens in a cell exposed to temperatures above 40c?

enzymes lose their shape

Small organisms in homeostasis

exchange water, dissolved materials and heat with the environment faster

Large organisms in homeostasis

more easily maintains a constant internal temperature and water balance

Tiny organisms in homeostasis

exchange heat, water and dissolved materials with their environment very quickly

Osmosis

diffusion of water across a selectively permeable membrane, increased solute concentration leads to a decreased water concentration

Passive Transport

the movement of substances across a cell membrane without the use of energy by the cell

The regulation of water and solutes in humans

controlled by the kidneys, the by product of protein metabolism (ammonia) is converted to urea in t he liver, urea is carried to the kidneys and eliminated in urine

Kidneys

filter blood from the renal arteries and produce urine as waste

Glomerulus

small network of capillaries encased in the upper end of a nephron where the filtration of blood takes place

Metabolic Heat

energy released within an organism during the process of cellular respiration

Endotherms

"warm blooded" animals that maintain a high body temperature in cold environments

Ectotherms

"cold blooded" animals that depend on environmental heat to maintain their body temperature

Macronutrients

elements that are needed in a large amount, represents 99% of the weight of an organism

Micronutrients

elements that are only needed in a small amount

Iodine

an essential trace mineral that is needed for the synthesis of thyroid hormones

Carbohydrates

the starches and sugars present in foods, used as a source of energy and carbon

Fats

concentrated source of energy

Essential Fats

fats that cannot be produced by the body and thus must be eaten, required to make certain compounds

Protein

source of amino acids, some amino acids can not be synthesized by the human body

Eight essential amino acids

tryptophan, methionine, valine, threonine, phenylalanine, leucine, isoleucine, lysine

Saliva

the fluid released when the mouth waters that plays an important role in both mechanical and chemical digestion

Amylase

enzyme in saliva that breaks the chemical bonds in starches transforming them into sugars, digests carbohydrates

Esophogus

tube in wich food travels from mouth to the stomach

Stomach

large muscular sac that continues the mechanical and chemical digestion of food

Small Intestine

the part of the digestive system in which most chemical digestion takes place.

Colon

another name for the large intestine, removes additional nutrients and water from food

The three steps of the animal digestive system

breakdown, absorption and waste

Specialized epithelial cells secrete ____ in the stomach

hydrochloric acid (HCI)

Mucous

protects stomach lining from the acids of the stomach

Proteases

secreted by epithelial cells, digests proteins

Peristalsis

waves of muscular contractions that move food through the digestive tract

Pancreas

regulates the level of sugar in the blood and produces insulin

Liver

produces bile

Villi

finger like projections of epithelial cells

Lipases

enzymes that break down lipids and digests fats

The normal flora

microorganisms that reside in or on the body without causing disease

Gastrin

hormone that causes the stomach to produce stomach acid

Secretin

digestive hormone that stimulates the pancreas to release bicarbonate to neutralize acid in duodenum

Ghrelin

hormone secreted by empty stomach; sends "I'm hungry" signals to the brain

Peptide YY

released by the gastrointestinal tract after a meal , inhibits appetite

Lactase

enzyme that breaks down lactose

Lactosis

lack of lactase, digestive problems with milk

Cellulase

enzyme that breaks down cellulose

Circulatory System

the cardiovascular system this system works as the transportation highway for the body, it consists of the heart, blood, and blood vessels, it transports substances such as oxygen, carbon dioxide, and nutrients in the body

Thick-walled Arteries

carry blood from the heart to the rest of the body

Tiny Capillaries

allows the exchange of materials between the blood and surrounding tissues

Thick-Walled veins

collect blood from the body and return it to the heart

Closed Circulatory System

a circulatory system in which the oxygen-carrying blood cells never leave the blood vessels

How many chambers are in a human heart?

4

Right Atrium

the right upper chamber of the heart that receives blood from the body and pumps it into the right ventricle

Right Ventricle

pumps deoxygenated blood to the lungs

Left Atrium

receives oxygenated blood from the lungs

Left Ventricle

pumps oxygenated blood to the body

What causes the lub heartbeat sound?

created when the one way valve between the atrium and the ventricle shuts

What causes the dub heartbeat sound?

occurs when the valve between the ventricle and arteries snaps shut

What is an ideal human blood pressure?

120 /80

Systolic blood pressure

the upper number in the fraction that measures the pressure in your arteries when your heart beats

Diastolic blood pressure

the lower number in the fraction that measures the pressure in your arteries when your heart rests between beats

Capillaries

extremely narrow blood vessels lined by a single layer of endothelial cells

Red Blood Cells

blood cells that carry oxygen from the lungs to the body cells, rich in hemoglobin

White Blood Cells

involved in defense against pathogens

Plasma

fluid portion of blood

What are the two main transport cells in a plant?

xylem and phloem

Xylem

nonliving vascular tissue that carries water and dissolved minerals from the roots of a plant to its leaves

Phloem

living vascular tissue that carries sugar and organic substances throughout a plant

Roots

absorbs water and minerals from the ground, anchors plant in ground

Companion Cells

transport sugar into the phloem cells in the leaf

Stem

supporting structure that connects roots and leaves and carries water and nutrients between them

Bud

plant structure containing undeveloped tissue that can produce new stems and leaves

Stomata

small openings on the underside of a leaf through which oxygen and carbon dioxide can move

What organ is responsible for humans to take in oxygen and release carbon dioxide?

lungs

Why do humans require lungs where as a bacterium does not?

bacterium and protists can simply diffuse gases through their plasma membranes to meet gas exchange needs

Respiratory System

a system of organs, functioning in the process of gas exchange between the body and the environment, consisting especially of the nose, nasal passages, nasopharynx, larynx, trachea, bronchi, and lungs

Lungs

elastic sacs that allow us to pump in large amounts of air

Trachea

windpipe

Alveoli

tiny sacs of lung tissue specialized for the movement of gases between air and blood

Gas Exchange

the process of obtaining oxygen from the environment and releasing carbon dioxide

What cell type makes up the walls of the alveoli?

thin epithelial

What function do epithelial cells provide for our lungs?

gas exchange

Hemoglobin

an iron-containing protein in red blood cells that reversibly binds oxygen

Epidermis

outermost layer of skin

Why did Charles Whitman commit the murders he committed?

large tumour in the middle of his brain, compressed the amygdala which deals with emotional regulation and fear and agression

Medulla Oblongata

coordinates information dealing with breathing rhythms, blood pressure, heart rate, digestion

Cerebellum

coordinates subconscious regulation of voluntary movements, regulates posture and balance

Midbrain

helps maintain muscle tone, sends some sensory data to higher brain centers in the forebrain

Hypothalamus

regulates homeostasis and integrates the nervous and endocrine systems

Limbic System

the "emotional brain" also involved in olfaction and memory, includes the amygdala

Thalamus

the "gateway to the consciousness" relaying information to and from the cerebrum

Cerebrum

responsible for our capacity to talk, calculate, create art, and consciously sense the world around us, divided into four lobes, occipital , temporal, parietal and frontal

Neuron

a specialized cell transmitting nerve impulses

Dendrite

antenna like parts of a neuron that are specialized to receive information.

Where is information processed in a cell?

the cell body

Axons

carry impulses away from the cell body

Axon Terminal

the endpoint of a neuron where neurotransmitters are stored