Cell Review - Bio Unit 3

What don’t prokaryotic cells have?

membrane-bound nucleus

What are the shapes of prokaryotes?

bacilli (rods)

spirilli (spirals)
cocci (spheres)

compartmetalization

the organization of a cell into distinct, membrane-bound compartments (like organelles) or other localized areas to perform specific functions more efficiently

What is allowed through the phospholipid bilayer?

small, nonpolar molecules (O2, CO2, some steroids, water)

Why are some things allowed through the phospholipid bilayer?

Because the hydrophillic tails allow nonpolar molecules through

What is not allowed through the phospholipid bilayer?

charged, large molecules (H+, Cl-, K+, proteins, sugars)

cytosol/cytoplasm

intracellular fluid

What is included in the nucleus of animal cells?

chromatin: uncondensed, loose DNA (multiple linear chromosomes)

nucleolus: ribosome synthesis

nuclear envelope: membrane w pores for mRNA and ribosomes to leave

ribosome

site of protein synthesis, reads rRNA, and bonds together amino acids

smooth endoplasmic reticulum

makes lipids and steroids, detoxifies liver cells, calcium storage

rough endoplasmic reticulum

has ribosomes to make proteins to leave the cell (via vesicle)

Golgi apparatus

modifies protein from endoplasmic reticulum, packages protein into vesicle to leave the cell

lysosome

contains hydrolases to break down molecules for reuse

mitochondrian

for cellular respiration, ATP synthesis from glucose with oxygen

peroxisome

catalase to break down H2O2

cytoskeleton

structural support, roads for vesicle/organelle movement

centrosome

where microtubules organize for cell division

vacuole

storage vesicle

What do animal cells sometimes have that helps with movement?

flagella or cilia

cell wall

around cell membrane, maintains water, shape, made of cellulose

plasmodesmata

pores in cell wall for exchange of material

chloroplast

contains chlorophyll to capture light for photosynthesis

How do chloroplasts perform photosynthesis?

they convert CO2 and water to glucose and O2

central vacuole

largest vacuole, stores water and solutes

What is evidence that supports endosymbiotic theory ?

Mitochondria and chloroplasts have a double membrane (inner and outer), have their own DNA and ribosomes, have circular DNA, 70s ribosomes, and reproduced via binary fission

passive transport

high to low concentration (down/with the concentration gradient)

active transport

low to high concentration (against the concentration gradient)

Why type of transport needs energy?

active

simple diffusion

the passive movement of small, uncharged molecules directly across a cell membrane, from an area of higher concentration to an area of lower concentration

is simple diffusion passive or active transport?

passive

facilitated diffusion

a cellular process where large or charged molecules move across a cell membrane from an area of high to low concentration, with the help of specific transmembrane proteins (channels or carriers)

is facilitated diffusion active or passive?

passive

osmosis

the facilitated diffusion of water based on solute concentration or tonicity

hypertonic solution

solution has more solute (less water) than cell

hypotonic solution

solution has less solute (more water) than cell

isotonic solution

solution has equal solute (equal water) as cell

What happens to a cell in a hypertonic solution?

The cell will shrivel because the solution wants the water from the cell to reach equilibrium

What happens to a cell in a hypotonic solution?

The cell will expand because the solution has too much water and will give some of it to the cell to reach equilibrium

What is required for active transport?

energy in the form of ATP, protein to facilitate movement

bulk transport

the energy-requiring movement of large quantities of substances (food, solutes) across cell membranes via vesicles

Which ways can bulk transport move?

endocytosis (taking in substances) and exocytosis (removing substances)

how does temperature affect diffusion rate?

increases

how does pressure affect diffusion rate?

increases

how does surface area affect diffusion rate?

increases

how does membrane thickness affect diffusion rate?

decreases

how does concentration gradient affect diffusion rate?

increases

how does molecular weight affect diffusion rate?

decreases

What is water potential?

A measurement of how likely water is to diffuse/do osmosis

How does water mover?

from high to low potential

What is the pressure potential of an open container?

zero

Which type of cell does not have a pressure potential?

animal cells