Ndebele Flashcards
what are the differences between Animal cells and plant cells?
Animal Cells:
a nucleus, cytoplasm, cell membrane, mitochondria and ribosomes
Plant and algal Cells: cell wall, and often have chloroplasts and a permanent vacuole
What is a nucleus?
The nucleus contains genetic material, which controls the activities of the cell. (found in animal and plant cells)
What is a Cytoplasm?
Most chemical processes take place here, controlled by enzymes. (found in animal and plant cells)
What is a Cell membrane?
Controls the movement of substances into and out of the cell. (found in animal and plant cells)
What is the Mitochondria?
Most energy is released by respiration here (found in animal and plant cells)
What is the Ribosome?
Protein synthesis happens here. (found in animal and plant cells)
What is the Cell wall?
Strengthens the cell (found in plant cells)
What is a chloroplast?
Contain chlorophyll, which absorbs light energy for photosynthesis (plant cells only)
What is a permanent vacuole?
Filled with cell sap to help keep the cell turgid.
turgid = swollen and firm with water
Define tissues in systemic terms?
A tissue is a group of specialised cells that have a similar structure and function. Tissues consist of groups of similar cells
What is and When does diffusion occur?
Diffusion occurs when particles spread. They move from a region where they are in high concentration to a region where they are in low concentration. Diffusion happens when the particles are free to move. This is true in gases and for particles dissolved in solutions. Particles diffuse down a concentration gradient, from an area of high concentration to an area of low concentration. This is how the smell of cooking travels around the house from the kitchen.
Define organs in systemic terms?
Organs contain different tissues, working together to carry out particular functions.
Define an organ system?
Organ systems contain different organs. The different organ systems work together in an organism.
Define the function of Muscular tissue?(A)
Contracts, bringing about movement
Define the function of Glandular tissue?(A)
Produces substances such as enzymes and hormones
What is an enzyme?(A)
proteins which catalyse or speed up chemical reactions within our bodies.
What is a hormone?(A)
Chemical messengers produced in glands and carried by the blood to specific organs in the body.
Define the function of Epithelial tissue?(A)
Covers some parts of the body
Function of Pancreas and salivary glands(A)
Produce digestive juices
Function of stomach(A)
digests food
Function of Liver(A)
produces bile
Function of Small intestine(A)
Digest and absorb soluble food
Function of Large intestine?(A)
Absorbs water from undigested food, producing faeces
Function of the Epidermal tissue(P)
Covers the plant
Function of the Mesophyll(P)
Carries out photosynthesis
Function of the Xylem and phloem(P)
Transport of substances around the plant
Give some examples of plant organs?
- Roots
- Stems
- Leaves
In Plants, What is the purpose of the Chlorophyll?
To absorb sunlight
In plants, what is the advantage of having a large surface area?
the plant can absorb more light
In plants, what is the purpose of the Stomata?
To let carbon dioxide diffuse into the leaf
In plants, what is the advantage of having a Network of veins?
To support the leaf and transport water and carbohydrates
In plants, What is the advantage of a Thin, waxy cuticle made of wax?
To protect the leaf without blocking out light
What is the name given to the process where food molecules are broken down into small, soluble ones, where they can enter the blood system?
digestion
When do enzymes work best?
Enzymes work best when they are at a warm temperature, if the temperature is too high, they can denature.
What can a Visking tube be used to represent?
the wall of the gut because it behaves similarly.
