Cells & Nutrition

What are the two main types of human cells?

SEX CELLS (gametes: sperm and oocytes) and SOMATIC cells (all other body cells)

What makes the cell membrane selectively permeable?

it allows certain substances to pass while blocking others

name 6 transport mechanisms across the cell membrane

Diffusion, Osomsis, Facilitated Diffusion, Active Transport, Endocytosis, Exocyctosis

What are two main types of cell division?

Meiosis and Mitosis

What is the result of meiosis?

Gametes with genetic variation (sperm and egg)

What is result of mitosis?

identical somatic cells (clones)

what is the role of cell membrane

creating a protective barrier, regulating the transport of substances into and out of the cell, facilitating cell-to-cell communication

what is diffusion?

passive movement of particles from an area of high concentration to an area of low concentration

What is osmosis?

the net movement of water molecules across a semipermeable membrane from an area of high water concentration to an area of low water concentration

what is facilitated diffusion?

a type of passive membrane transport that moves molecules like polar substances and ions across a cell membrane down their concentration gradient

what is active transport?

movement of substance against concentration gradient, requires energy

list 6 possible causes of cell injury

Hypoxia

Ischemia

chemical injury

infectious injury

immunologic injury

physical damage

inflammation

What are 3 causes of hypoxia

low oxygen in air

loss of hemoglobin

respiratory/cardiovascular diseasew

what can cause chemical cell injury

poisons

lead

carbon monoxide

ethanol

how do infectious agents damage cells

through direct action

toxic production

triggering inflammation

what is nutrition

study of nutrients and how body uses them

name the macronutrients

carbohydrates, lipids, proteinsna

name the micronutrients

vitamins and minerals

how many calories per grab do carbs, proteins, and fats yeild?

carbs = 4, proteins = 4, fats = 9

what does the body metabolize for energy in order?

Glucose → glycogen → fats/proteins

what is metabolism

chemical changes in cells that support growth, energy, repair, waste removal, and homeostasis

what do enzymes do

catalyze biochemical reactions by lowering activation energy

3 stages of aerobic respiration?

Glycolysis, citric acid cycle (TCA cycle), electron transport chain

how many ATP per glucose are produced in aerobic respiration

up to 36 ATP

what are the end products of glucose oxidation

carbon dioxide, water, and ATP

what is homeostasis

stability of the bodys internal environment

what are the two types of body fluids

intracellular (inside body), extracellular (outside body)

what can significant fluid loss cause?

shock, disrupting homeostasis