Biology tricky topics test

Metabolism includes -

Conversion of glucose to starch and glycogen to cellulose

Formation of lipids from molecules of glycerol

use of glucose and nitrate ions t form amino acids

respiration

breakdown excess proteins

Effects osmosis has on a plant cell

swell up until their cytoplasm and cell membrane are pushing against their cell wall. They are said to be turgid .

Effects osmosis has on animal cells

They do not have a cell wall, so will change size and shape when put into solutions 

Role of digestive enzymes ?

Convert large food molecules into small solluable molecules that can be absorbed into the bloodstream

Carbohydrases

Break down to carbohydrate to simple sugars

Amylase

A carb which breaks down starch into glucose

Proteases

Breaks down protiens to amino acids

Lipases

Break down to lipids (fat) to glycerol and fatty acids

structures in a leaf

Epidermis

palisade and spongy mesophyll

xylem and phloem

guard cells surrounding stomata

Photosynthesis equation

Carbon dioxide + water ----} glucose + oxygen

process of transpiration

When the plant opens its stomata to let in carbon dioxide, water on the surface of the cells of the spongy mesophyll and palisade mesophyll evaporates and diffuses out of the leaf

Translocation

**Translocation** is the movement of sugar produced in photosynthesis to all other parts of the plant for respiration and the other processes described above. This occurs in **phloem** cells.

Physical defense system plants

cellulose cell walls

tough waxy cuticle

layers of dead cells around stem/bark

Mechanical defense systems plants

thorns and hairs

leaves which droop or curl when touched

mimicry to trick animals

chemical defence response

antibacterial chemicals - witch hazel

poisons to deter herbivores

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Steps of monoclonal antiobodies 1

mouse lymphocytes stimulated to produce a particular antibody

Steps of monoclonal antibodies 2

lymphocytes are combined with a tumor cell to form a hybridoma cells

steps of monolconal antibodies 3

Hybridoma cells both divide and make the antibody

Step 4 monoclonal antibodies

Single hybridoma cells are cloned to produce many identical cells that all produce the same antibody

Uses of monoclonal antibodies

Pregnancy tests

used in chemical experiments

in research

treat some diseases like cancer

Risk factors for disease

Diet - CHD

obsesity - type 2 diabetes

alchohol - brain and liver

smoking - lungs \]

smoking - unborn babies

radiation - cancers

Stage 1 of cell cycle

Interphase - before a cell can divide it needs to grow and increase the number of subsecullar structures, The DNA replicates to form 2 copies of each chromosone

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Stage 2 of cell cycle

Mitosis - 1 set of chromosones is pulled to each end of the cell and the nucleus divides

stage 3 of cell cycle

Cytokenisis - cytoplasm and cell membrane divides to form 2 identical cells

Examples of specialised cells

Sperm cells

nerve cells

muscle cells

root hair cells

xylem

phloem