Chapter 1: Cells Flashcards
1
Q
definition of a cell
A
- a unit of life
- consists of a mass of living matter (protoplasm)
2
Q
cell membrane
A
- surrounds cytoplasm
- made out of lipids and proteins
- partially permeable membrane
- controls movement of substances in & out cell
3
Q
cell wall (PLANTS ONLY)
A
- encloses entire plant cell, surrounds cell membrane
- made up of cellulose
- gives cell fixed shape, protect from injury
- fully permeable
4
Q
cytoplasm
A
- jelly-like substance
- where most cell activities occur
- contains organelles
5
Q
nucleus
A
- contains genetic info
- controls cell activities
- essential for cell division
6
Q
Rough Endoplasmic Reticulum (RER)
A
- network of flattened spaces
- surface appears rough under EM (attached ribosomes)
- outer surface continuous with nuclear membrane
# transports proteins (made by ribosomes) to Golgi body for secretion out of cell
7
Q
Ribosomes
A
- small round structure
- attached to membrane of RER/lies freely in cytoplasm
- needed to synthesis proteins
+ ribosomes attached to RER make proteins r usually transported out of cell
+ ribosomes lying freely in cytoplasm used to make proteins for that cell
8
Q
Smooth Endoplasmic Reticulum(SER)
A
- no ribosomes attached to membrane
- more tubular & connected to RER
- synthesises fats and steroids
- detoxification: converts harmful substances into harmless substances
9
Q
Golgi body
A
- shaped like a disc; consists of flattened spaces surrounded by membrane
- vesicles seen fusing with one side of Golgi body & pinching off opposite
- chemically modifies substances
- stores & packages these substances vesicles for secretion out of cell
10
Q
mitochondria
A
- small oval or sausage-shaped organelle
- aerobic respiration occurs
+ food substances broken down to release energy
+ energy used by cell to perform activities such as growth & reproduction
11
Q
chloroplast
A
- oval structures
- contains green pigment (chlorophyll)
- essential for photosynthesis
12
Q
vacuole
A
- fluid-filled space enclosed by partially permeable membrane
- store substances within cell
- plants have large central vacuole (contains cell sap- sugars, mineral salts, amino acids),
animals have many small vacuoles (water & food substances- exist temporarily)
13
Q
RBC Adaptation to Function
A
- contains haemoglobin: binds to oxygen and transports it ard body
- circular, biconcave shape: increases SA:V to allow O2 to diffuse in and out at a higher rate
- lacks a nucleus: enables cell to store more haemoglobin for transport of oxygen
- flexible: squeeze thru capillaries easily
14
Q
Muscle Cell Adaptation to Function
A
- elongated and cylindrical shape: contains many nuclei & mitochondria
- has mitochondria: provide energy for contraction of muscle cell
15
Q
Root Hair Cell Adaptation to Function
A
- long narrow root hair: increase SA:V to absorb water & minerals at a higher rate
