Ch.2 Cells Flashcards
Parts of the animal cell
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Parts of plant cell
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Cell parts in common
Mitochondria, ribosomes, cell membrane, nucleus, cytoplasm
Only in plant cells
Chloroplast, vacuole, cell wall
Nucleus
Controls cell activities eg cell growth and repair of worn out parts
Contains genetic material
Needed for cell division
Cytoplasm
Contains mostly water and dissolved substances eg sugars, proteins and salts
Jelly-like substance between cell membrane and nucleus
Holds all cell parts together
Medium for biochemical reactions
Cell membrane
Made of lipids and proteins
Partially permeable
Controls the movement of substances in and out of the cell
Mitochondria
Converts energy stored in food into usable energy (ATP) through aerobic cellular respiration
Ribosomes
Needed to make proteins in the cell
Cell wall
Made mainly of cellulose
Protects cell from injury
Gives the plant cell a fixed shape/supports it
Fully permeable, so it cannot control types of substances that enter/leave cell
Vacuole
Fluid-filled space enclosed by a membrane
Contains cell sap to help keep the cell turgid. This cell sap includes dissolved substances like sugars, mineral ions and amino acids
The only animal cells with vacuoles are amoeba and paramecium
Chloroplasts
Contain chlorophyll for photosynthesis - the process by which plants make food
Bacterial cell
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Animal cell vs plant cell - food reserve
Animal - glycogen (stored in liver + muscle in humans)
Plant - starch
Differentiation
A cell becomes specialized for a specific function. New cells are produced through the division of existing cells
RBC (red blood cell)
- Biconcave disc shape
- Increase surface area, therefore taking in and releasing oxygen more quickly - No nucleus
- Contains more haemoglobin to transport more oxygen
FUNCTION: Carries oxygen from lungs to body and carbon dioxide from body back to the lungs
Ciliated cell
- Lines the trachea and bronchi
- Tiny hair-like structures called cilia
FUNCTION:
1. Respiratory system
- Cilia helps to move mucus and dust-trapped particles up the trachea and bronchi, preventing it from entering the lungs
2. Reproductive system
- Move egg
Neurones/nerve cell
- Long nerve fibre to carry out function
- Nerve fibre insulated by fatty materials called myelin sheath - speeds up transmission
- Branches at both ends to connect to other neurones
FUNCTION: Transmits (sends and receives) information in the form of electrical impulses
Egg cell
- Large nucleus to carry genetic information
- Abundant cytoplasm containing a small amount of yolk, providing nutrients for the early development of the embryo
- Outer jelly coat. After the sperm enters, it will thicken to prevent other sperms from entering.
FUNCTION: Carry mother’s DNA/genetic information
Sperm cell
- Long tail to swim towards egg
- Head has a nucleus containing genetic information
- Numerous mitochondria which releases energy for sperm to actively swim on its own
FUNCTION: Carry dad’s genetic information to egg
Root hair cell
- Long, narrow extension which increases surface area to absorb more water in the soil
- Thin cell wall which allows water to pass through easily.
- No chloroplasts because it is located underground (no sunlight). Therefore, there is no point to have chloroplasts.
FUNCTION: Absorbs mineral ions and water from the soil.
Palisade mesophyll cell
- Long, cylindrical-shaped - large surface area for exposure to light.
- Found near the upper surface (top) of a leaf
- PACKED with chloroplasts to absorb as much sunlight as possible for photosynthesis
FUNCTION: Carry out photosynthesis
What makes an organism?
CT OOO
Cell, tissue, organ, organ system, organism
Cell definition
Simplest units showing the characteristics of life, often dubbed ‘building blocks of life’.
Tissue definition
Group of cells working together to carry out a specific function
Organism definition
Multiple organ systems working together to form an organism
Magnification formula
I AM.
Magnification = Image size/Actual size
Micrometre
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Mm to micrometer
x1000