Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology > P1 12 Cell structure+ transport > Flashcards

P1 12 Cell structure+ transport Flashcards

(48 cards)

Start Studying
1
Q

sub-cellular structure of animal cells

A
  • nucleus
  • cell membrane
  • cytoplasm
  • mitochondria
  • ribosomes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

sub-cellular structure of plant cells

A
  • nucleus
  • cell membrane
  • cytoplasm
  • mitochondria
  • ribosomes
  • vacuole
  • chloroplasts
  • cell wall
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

function of the nucleus

A

contains genetic material

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

function of the cell membrane

A

semi-permeable - controls what goes in+out of cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

function of the cytoplasm

A

holds all organelles, where a cell’s chemical reactions take place

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

function of mitochondria

A

where chemical reactions take place
eg. respiration - releases the energy stored in glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

function of ribosomes

A

where protein-synthesis happens, produces protein for the cell to grow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

function of the vacuole

A

contains cell sap, keeps cell turgid (rigid), stores water+cell waste, prevents cell from bursting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

function of chloroplasts

A

where photosynthesis takes place, contains chlorophyll

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

function of the cell wall

A

made of cellulose, supports/protects the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

describe prokaryotic cells

A

single-celled organisms, very small, genetic material not enclosed in a nucleus, circular DNA, eg. bacteria cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

describe eukaryotic cells

A
  • found in animals+plants/fungi+protists
  • genetic material enclosed in a nucleus, cell membrane+cytoplasm
  • eg. animal/plant cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

differences between eukaryotic+prokaryotic cells (4)

A
  • e has nucleus, not p
  • e DNA in nucleus, p DNA free in cytoplasm
  • p are smaller
  • e has mitochondria, not p
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

state the equation for magnification

A

magnification = size of image / size of actual object
M = I / A
(image and actual must be in the same units, eg. mm/cm)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

state the equation for total magnification using a light microscope

A

total M = M of eyepiece lens x M of objective lens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

describe light microscopes (5)

A
  • invented first (1600s)
  • uses a beam of light to form a 2D image of an object
  • can magnify living specimens
  • only reaches x2000 magnification and low resolution
  • cheaper+ easy to use
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

describe electron microscopes (5)

A
  • invented last (1930s)
  • uses a beam of electrons to form a 3D image of an object
  • cannot use live specimens
  • reaches x2,000,000 magnification and high resolution- smaller things can be seen in more detail
  • large+ expensive+ kept in special conditions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

define resolution

A

the ability to distinguish between two separate points
(process of separating something into two parts)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

state units for measuring microscopic objects (4)

A

millimetres (mm)
micrometres (μm) /1,000
nanometres (nm) /1,000,000
picometres (pm) /1,000,000,000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

state steps for microscopy practical

Study These Flashcards
A

PREPARE SLIDES
* add drop of water onto glass slide
* add epidermal tissue (onion layer)
* add drop of iodine (or methylene blue for human cheek cells) to stain cell
* place cover slip on top
USE
* clip slide onto stage
* ensure lowest-powered objective lens is over the slide
* turn coarse focus until the stage is just below the lens
* look down eyepiece+ turn coarse focus knob towards you until the image is roughly in focus
* adjust fine focus knob until image is clear
* record a LOW POWER IMAGE (shows arrangement of regions of tissue+ individual cells)
* change objective lens to a higher power and bring slide back into focus (w/ coarse+ fine knobs)
* record a HIGH POWER IMAGE (detailed image showing a single cell)

21
Q

adaptations of sperm cells (4)

Study These Flashcards
A

fertilise an egg cell
* long tail+ streamlined shape: for movement+ swimming
* lots of mitochondria: provide energy for tail movement
* haploid nucleus: contains half genetics/ number of chromosomes
* digestive enzymes in acrosome: help break down the egg membrane

22
Q

adaptations of nerve cells (4)

Study These Flashcards
A

carries electrical impulses around body
* lots of dendrites: make connections to other cells
* synapses: pass impulses between nerve cells
* lots of mitochondria in synapses: provides energy for transmitting impulses
* long axon: carries impulses to different cells

23
Q

adaptations of muscle cells (3)

Study These Flashcards
A

contract and relax to allow muscle movement
* contains fibres: slide over each other to contract
* lots of mitochondria: provide energy for contraction
* store glucose as glycogen: can be converted to glucose for respiration

24
Q

define differentiation

Study These Flashcards
A

process of a cell becoming specialised for a specific function
* most animal cells differentiate early in life whereas plant cells retain ability throughout their life
* eg. cells in bone marrow differentiate into red blood cells- lose their nucleus+ become filled w red oxygen-carrying haemoglobin pigment

25
adaptations of root hair cells (2)
absorb water+minerals from soil * large surface area: faster water absorption (osmosis) * lots of mitochondria: provide energy for active transport of minerals (soil->cell)
26
adaptations of phloem cells (2)
transport sucrose/amino acids around plants * sieve tubes: no nucleus, perforated ends so cytoplasm connects cells-> sugars are translocated within cytoplasm of cells * attached companion cells to tubes: have mitochondria which supply energy that cytoplasm usually stores (as cell only has a thin layer of cytoplasm)
27
function of phloem cells
transport food (sucrose/amino acids) made in leaves from photosynthesis to rest of plant
28
adaptations of xylem cells (2)
transports water+minerals up from roots to highest leaves/shoots * long hollow tubes: transports water -> tubes are hollow as made from dead cells that have lost their cytoplasm * walls thickened with lignin: provides strength to withstand pressure from water uptake
29
function of xylem cells
transport water+minerals up from roots to highest leaves/shoots
30
differences between xylem and phloem cells (5)
XYLEM * transports water+ minerals * made up of dead cells, no cytoplasm * impermeable to water * transports one way up the plant (transpiration) * passive process PHLOEM * transports sucrose+ amino acids * made of living cells+ cytoplasm (thin layer) * permeable to allow water to pass through * transports around the plant (translocation between cells) * active transport
31
describe diffusion
* the movement of particles from an area of high to low concentration * passive process- doesn't require energy * across cell membranes to enable movement of substances in+out * eg. oxygen diffuses into blood in capillaries+ carbon dioxide diffuses into the air in the alveoli
32
factors increasing rate of diffusion (4)
* higher concentration gradient * larger surface area * shorter diffusion distance (thinner walls) * higher temp (particles have more energy so move quicker)
33
describe active transport
* movement of substances from a low to high concentration through a semi-permeable membrane * requires energy as substances move against concentration gradient * eg. minerals from soil into root hair cells/ sugars from gut into blood
34
describe osmosis
* movement of water from a high to low concentration through a semi-permeable membrane * passive process- doesn't require energy * large molecules (salt) cannot pass through membrane * eg. water from soil into root hair cells
35
describe steps for osmosis RP
* cut potato into evenly sized cylinders (so they have the same surface area) * pour different concentrations of salt/sugar solution into beakers * measure the original mass of each cylinder using a balance and place one into each beaker for 24hrs/a day.. * remove cylinders, pat dry, measure the new mass * calculate change in mass (new mass-original mass) * then percentage change in mass of each potato change/initial x100
36
define a hypotonic vs hypertonic solution +exs
hypo: higher conc. of water in the solution (than in cell) eg. pure (distilled) water -> water moves into the cell hyper: lower conc. of water in the solution (than in cell) eg. salt water -> water moves out of cell
37
describe what happens to a plant and animal cell when placed in a hypotonic solution
HIGHER concentration of water outside the cell (in the solution)- water moves into cell (eg. pure water) plant: becomes turgid (normal) - cell wall +vacuole prevents cell from bursting animal: becomes lysed (process of lysis) - cell bursts
38
describe what happens to a plant and animal cell when placed in a hypertonic solution
LOWER concentration of water outside the cell (in the solution)- water moves out of cell (eg. salt water) plant: becomes plasmolysed (plasmolysis) - cytoplasm+membrane shrink - plant wilts animal: becomes shrivelled/ crenated - cell dies
39
describe what happens to a plant and animal cell when placed in an isotonic solution
SAME concentration of water inside+outside cell- no net movement plant: becomes flaccid - doesn't provide plant with much support as they lack stiffness/strength animal: is normal
40
describe pros+cons of using stems cells for medical treatment
/ replace damaged cells+ repair tissues, help conditions such as type 1 diabetes+ paralysis X if stem cells used from a donor the patient's immune system may attack+reject new cells, viral infections can be transferred in stem cells
41
describe pros+cons of embryonic stem cells
embryos are cloned+ made to develop into desired cells / can develop into most cell types X ethical/ religious objections: embryos are destroyed when obtaining stem cells
42
describe pros+cons of adult stem cells
eg. bone marrow can naturally form blood cells / no ethical objections X can only differentiate into some cell types
43
describe process of therapeutic cloning
* a nucleus is taken from a cell of a patient and transplanted into a donor's unfertilised egg cell * cell develops into an embryo * produce stem cells which are genetically identical to those of the patient (so will not be rejected) * stem cells removed+cultured in lab and transferred to patient
44
describe 2 uses of plant stem cells
* rare species cloned to protect from extinction * valuable species with beneficial features (disease resistance) are cloned to produce larger yield
45
benefit of plant stem cells
can differentiate into all types of plant cells throughout the plant's life
46
where are plant stem cells found
in the meristems at the tips of roots+shoots
47
3 stages of cell cycle
* cell growth: DNA replicates * mitosis: one set of chromosomes moves to each end of cell, nucleus divides * cytoplasm+cell membrane divide, forms 2 genetically identical cells
48
4 simple steps of mitosis
* DNA replicates * chromosomes pulled apart into two sets, nucleus divides * cytoplasm divides into two * cell membrane divides - two identical cells formed

Biology (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions