scientific method/cell structure

Question 1

Cell membrane

Answer 1

outer boundary of cell

Question 2

Organelles

Answer 2

structures suspended in cytoplasm

Question 3

Cytoskeleton

Answer 3

internal scaffolding of protein fibres within cytoplasm

Question 4

Cell membrane

Answer 4

separates cell contents from outside of cell.
Controls what goes in and out of cell.
Very thin.

Question 5

cytoplasm

Answer 5

Jelly-like or watery material inside cell that fills all space

Question 6

cytosol

Answer 6

Liquid part of cytoplasm.
75-90% water
Mixture of dissolved substances.
compounds suspended in watery fluid.
Where most metabolic reactions occur.
plays role in osmotic pressure and flow of chemicals in and out of cell.

Question 7

Organelles

Answer 7

structure within a cell

Question 8

Nucleus

Answer 8

largest organelle
Nuclear pores to allow large molecules in and out
Stores dna

Question 9

DNA

Answer 9

Deoxyribonucleic acid
Long strands when cell not splitting
chromosomes when cell is splitting

Question 10

Nucleolus

Answer 10

manufactures protein inside nucleus

Question 11

ribosomes

Answer 11

very small, spherical organelles

Amino acids joined together to make proteins

Question 12

endoplasmic reticulum

Answer 12

Provide surface for chemical reactions
channels for storing or transporting molecules.
Rough when ribosomes
smooth without ribosomes

Question 13

Golgi apparatus

Answer 13

series of flattened membranes stacked one upon other.

Vesicles formed at the edges.

Question 14

vesicles

Answer 14

Small sacs of liquid containing proteins

Question 15

lysosomes

Answer 15

Small sphere bound by membrane.
formed from Golgi.
Contain digestive enzymes.
when liquids/particles enter cell they form vesicles in the cytoplasm, then lysosome join with vesicles and break them down.
Digest worn out organelles.

Question 16

mitochondria

Answer 16

Spherical/sausage shaped.
spread across cytoplasm.
Has double membrane.
smooth outer membrane surrounds mitochondrion.
Inner membrane, cristae, arranged into series of folds extending into interior of organelles.
cellular respiration.
Inner membrane has greater surface area for chemical reactions.

Question 17

cilia and flagella

Answer 17

To move
Cilia - short, numerous projections
flagella - longer one or two projections

Question 18

Cytoskeleton

Answer 18

framework of protein fibres that give cell shape and assists cell movement.
Two types: microtubules, microfilaments

Question 19

Microtubules

Answer 19

hollow rods that keep organelles in place or move them around

Question 20

microfilaments

Answer 20

Move materials around the cytoplasm or move whole cell

Question 21

inclusions

Answer 21

Chemical substance not part of cell structure but found in cytoplasms.

Question 22

Surface area

Answer 22

represents the cells ability to take in enough nutrients and gets rid of waste.

Question 22

volume

Answer 22

all contents of the cell that needs nutrients and to get rid of waste

Question 22

Immediate environment

Answer 22

fluid that surrounds it; tissue fluid or extracellular fluid

Question 22

Extracellular fluid

Answer 22

allows continual exchange of materials in and out of cells.

Question 22

Homeostasis

Answer 22

body systems work together to ensure cellular environment, kept constant.
Cells maintained at constant temperature, fluids around have constant concentration

Question 22

fluid mosaic model

Answer 22

Membrane is fluid.
composed of phospholipid molecule, lipid molecules contain phosphate group
Arranged in two layers

Question 22

phospholipid

Answer 22

Have head and tail.
head is hydrophilic, face outwards
Tail is hydrophobic, face inwards

Question 22

four types of proteins in membrane

Answer 22

Receptor proteins
channel proteins
Carrier proteins
cell identity marker

Question 22

Functions of memrane

Answer 22

acts as physical barrier
Regulates passage of materials
sensitive to changes
Helps support the cell

Question 22

transport through cell

Answer 22

simple diffusion
Facilitated transport
vesicular transport

Question 22

Simple diffusion

Answer 22

spreading out of molecules so evenly spaced over space available
Concentration gradient
net diffusion

Question 22

Concentration gradient

Answer 22

greater the difference in concentration, the steeper the diffusion gradient and faster the rate of diffusion

Question 22

Net diffusion

Answer 22

movement of molecules from higher concentration to lower concentration gradient.
Happens because some molecules move opposite way.
when same amounts molecules move in same direction.

Question 22

Osmosis

Answer 22

diffusion of solvent through differentially permeable membrane in order to balance concentration of another substance.
Water will osmosis to balance concentration of solutes.

Question 22

osmotic pressure

Answer 22

The higher the concentration of solute, the higher the osmotic pressure.

Question 22

facilitated transport

Answer 22

Proteins in membrane allow molecules to be transported across the membrane.
when substances transport along concentration gradient, from higher to lower.
Passive

Question 22

active transport

Answer 22

Requires energy (ATP)
molecules transported against concentration gradient.
Doesn’t depend on concentration gradient.

Question 22

vesicular transport

Answer 22

Movement of substances across cell membrane in vesicles.
active
endocytosis
Exocytosis

Question 23

endocytosis

Answer 23

Taking liquid into cell by vesicular transport
pinocytosis
Phagocytosis

Question 24

pinocytosis

Answer 24

Take in liquids

Question 25

Phagocytosis

Answer 25

take in solids

Question 26

Exocytosis

Answer 26

when contents of vesicle inside cell are passed to the outside
Vesicle fuses wt membrane, contents of vesicle get pushed out into extracellular fluid.

Question 27

Isotonic

Answer 27

concentration of solute inside cell is same as outside.

Question 28

Hypertonic

Answer 28

environment outside of cell has higher concentration of solute

Question 29

Hypotonic

Answer 29

environment outside of cell has higher concentration of solute