Biology

Knowledge Organiser

Define Movement (MRS H GREN)

ability of an organism or part of n organism to change its position

define respiration (MRS H GREN)

a chemical reaction that occurs in cells and releases energy from glucose

Define sensitivity (MRS H GREN)

ability to detect and respond to changes in the surroundings

Define Homeostasis

maintenance of constant internal environment

Define growth (MRS H GREN)

permanent increase in dry mass

define reproduction

the process of creating new organisms

define excretion

the removal of metabolic waste

define nutrition

the means of obtaining food

function of the nucleus

controls the cell and contains the cell’s DNA

function of the cell membrane

controls what goes into and out of cells

function of cytoplasm

the place where chemical reactions occur

function of ribosomes

site of protein synthesis

what are the 3 plant cell structures not found in animal cells

1. cell wall

2. chloroplast

3. vacuole

function of cell wall + what its made of

Helps to maintain cell shape and structure (made of cellulose)

function of chloroplast

site of photosynthesis

function of vacuole

contains cell sap and provides support for the cell

how do you convert mm to um

multiply by 1000

image size = ??

actual size x magnification

define organelle

small structure within a cell that caries out a particular function

define cell

the basic building block of life

define tissue

a group of similar specialised cells working together to perform a particular function

define organ

a group of tissues working together to perform a particular function

define organ system

a group of organs working together to perform a particular function

what 2 groups does carbohydrates split into

1. glucose

2. starch/glycogen

what is the diagram of the molecules of starch/glycogen

chains of glucose (hexagons)

what is the molecule diagram for glucose

a hexagon

what elements are in glucose (carbohydrates)

Carbon, Hydrogen, Oxygen

what is the function of carbohydrates (glucose/starch/glycogen)

energy

what elements are in starch/glycogen (carbohydrates)

carbon, hydrogen, oxygen

what does the molecule diagram for proteins look like

chain of ovals

what molecule is protein made up of

amino acids

what elements make up protein (amino acids)

carbon, hydrogen, oxygen, nitrogen, sulfur

function of protein

growth and repair

what molecules are lipids made up of

glycerol and 3 fatty acids

what elements are lipids made up of

carbon, hydrogen, oxygen

function of lipids

insulation and energy storage

chemical test for starch

test with iodine, no heat required

colour change - brown/orange to blue/black

chemical test for glucose

test with benedict’s, heat required

colour change - blue to green/yellow/orange/brick red depends on levels

chemical test for protein

test with biurets, no heat required

colour change - blue to lilac

chemical test for lipids

test with ethanol and distilled water, no heat needed

colour change - colourless then forms white emulsion

What is an enzyme? (MA)

An enzyme is a biological catalyst that speeds up the rate of reaction without being used up. Enzymes have an active site with a specific shape that fits with a complementary substate to form an enzyme-substrate complex.

Temperature effect on enzyme activity (0-40*C) (4 points)

1. enzymes and substrates gain kinetic energy

2. more frequent collisions between enzyme and substrate

3. more enzyme-substrate complexes formed

4. enzyme activity increases up until the optimum temperature

temperature effect on enzyme activity (40-60*C) (4 points)

1. above optimum temperature the enzyme starts to denature

2. this causes the active site to change shape the substrate no longer fits and enzyme-substrate complexes cannot be formed

3. enzyme activity decreases

what is 40*C to enzymes and what happens when the temperature rises over it

it is the optimum temperature, enzymes denature over 40*C

define diffusion

the net movement of particles from an area of high concentration to an area of low concentration

define osmosis

the movement of water from an area of high water potential to an area of low water potential through a partially permeable membrane

define active transport

the movement of particles from an area of low concentration to an area of high concentration using energy

diffusion is _______ - no ________ is required

passive, energy

what are the four factors affecting the rate of diffusion

1. surface area to volume ratio (SA:vol)

2. diffusion distance

3. temperature

4. concentration gradient

how does SA:vol ratio affect the rate of diffusion

the larger the cube, the smaller the SA:vol ratio. Diffusion is slower in big organisms

how does diffusion distance affect the rate of diffusion

the larger the cube, the bigger the distance for particles to travel. Diffusion is slower in big organisms.

how does temperature affect the rate of diffusion

the colder the temperature, the slower the particles move. Diffusion is slower in cold temperatures.

How does concentration gradient affect the rate of diffusion

the smaller the difference in concentration, the slower the particles travel. Diffusion is slower when a shallow concentration gradient is present.

how to find volume

base x height x length

how to find surface area

area of one face x number of faces

Explain what has happened in the diagram (MA) (5 points)

1. there is a higher water potential inside/outside of the cell

2. water moves from the area of high water potential inside/outside of the cell, to an area of low water potential inside/outside the cell

3. across a partially permeable membrane

4. the cell gains/loses mass

5. the movement of water is called osmosis

is active transport passive?

no - it requires a membrane

Why do animal cells burst when placed in solutions with a high water potential, but plant cells do not?

Animal cells have no cell walls, plant cells do.

When placed in solutions with a high water potential, the water moves from the area of higher water potential to to the area with a lower water potential through the partially permeable membrane.

The cell expands as water enters and the cell becomes turgid

(water is moving out of cell the water leaves and cell becomes flaccid)

once too much water has entered, the cell bursts

Waterlogged soils do not contain much oxygen. Why then does the overwatered plant look unhealthy?

Active transport requires energy in the form of ATP to be able to move particles from low to high concentration.

The ATP comes from aerobic respiration that takes place in the mitochondria of plant root cells.

Oxygen is required for aerobic respiration to occur.

Define respiration

A chemical reaction that occurs in cells and releases energy from glucose.

Define alveoli

the air sacs in the lungs where gases diffuse between the air in the lungs and the blood in the capillaries.

Aerobic respiration word equation

Glucose + oxygen → carbon dioxide + water

aerobic respiration chemical equation (balanced)

C6 H12 O6 + 6 O2 → 6 CO2 + 6 H20

anaerobic respiration equation (in animals)

glucose → lactic acid

anaerobic respiration (in plants and fungi)

glucose → ethanol + carbon dioxide

Respiration does not produce energy but what does it do with energy?

Releases it in the form of ATP

what can energy in the form of ATP be used for (4 points)

1. active transport

2. muscle contraction

3. keeping warm

4. building large molecules from smaller ones (e.g. making proteins from amino acids)

what are the 4 key differences between Aerobic and anaerobic respiration

1. Anaerobic respiration requires oxygen, anaerobic does not

2. aerobic respiration releases more energy than anaerobic respiration

3. aerobic respiration occurs in the mitochondria whilst anaerobic respiration occurs in the cytoplasm

4. aerobic produces carbon dioxide and water whilst anaerobic respiration produces lactic acid (in animals) or ethanol and carbon dioxide (in plants/fungi)