Unit 2 : Organisation of the Organism

Question 1

6 Features that all eukaryotic cells / animal cells have

Answer 1

cell membrane, cytoplasm, nucleus, mitochondria, ribosome, endoplasmic reticulum

Question 2

Define Cell Membrane

Answer 2

controls movement in and out of cells

Question 3

Define Cytoplasm

Answer 3

jelly like substance which is the site of most chemical reactions in the cell

Question 4

Define Nucleus

Answer 4

spherical structure that contains cell’s DNA/genetic code and controls activities of the cell and cell division

Question 5

Define Mitochondria

Answer 5

where aerobic respiration happens

Question 6

Define Ribosome

Answer 6

allows protein synthesis in the cytoplasm

Question 7

Define Endoplasmic Reticulum

Answer 7

studded with ribosomes, it looks rough under the microscope

Question 8

3 Features that only Plant Cells contain

Answer 8

vacuole, cell wall, chloroplasts

Question 9

Define Vacuole

Answer 9

cell sap to keep cell turgid

Question 10

Define Cell Wall

Answer 10

rigid to hold the shape of the cell, strengthens the cell

Question 11

Define Chloroplasts

Answer 11

contains chlorophyll, which absorbs light energy for photosynthesis

Question 12

2 Features that Prokaryotes Lack

Answer 12

mitochondria and a true nucleus

Question 13

Define Plasmids

Answer 13

small, circular rings of DNA in the cytoplasm with extra genes outside the chromosomal DNA

Question 14

2 Specialised Features of a Root Hair Cell

Answer 14

1. absorbs water + dissolved mineral ions from soil
2. has hair like projection to provide larger area / larger surface area to volume ratio for absorption to happen

Question 15

1 Specialised Feature of Ciliated Cells

Answer 15

has cilia ( hair-like structure ) that helps with the movements of mucus up to the throat where it can be swallowed

Question 16

1 Specialised Feature of Palisade Mesophyll Cells

Answer 16

packed with chloroplasts and tall, elongated cells packed together to increase surface area

Question 17

2 Specialised Features of eurones

Answer 17

1. long extensions of neurons called dendrites are axons that help in sending impulses
2. dendrites receive signals and impulses while the axon sends signals to other neurons or tissue

Question 18

3 Specialised Features of Red Blood Cells

Answer 18

1. biconcave shape to maximise surface area to absorb oxygen.
2. thin cell membrane so gases easily diffuse through
3. no nucleus to increase space for more oxygen

Question 19

2 Specialised Features of Sperm Cells

Answer 19

1. acrosome is a cap on the head that assists with penetration of the jelly coating of the ovum
2. flagellum is the tail of the sperm. It undulates to help in moving and navigating through the female reproductive system

Question 20

2 Specialised Features of Egg Cells

Answer 20

1. large energy stores / nutrients for the growing embryo
2. jelly coating ( zona pellucida ). after one sperm cell penetrates the initial jelly coating, the coating become impenetrable to other sperm cells

Question 21

What are the Levels Of Organisation

Answer 21

cells - tissue - organ - organ system - organism

Question 22

Define Cells

Answer 22

the basic structural and functional unit of all forms of life

Question 23

Define Tissue

Answer 23

a group of cells with similar structures and hich work together to carry out a shared function

Question 24

Define Organ

Answer 24

a group of tissues which work together to carry out specific functions

Question 25

Define Organ Systems

Answer 25

a group of organs with related functions which work together to carry out body functions

Question 26

Formula for Magnifiction

Answer 26

magnification = image size ÷ actual size

Question 27

Define Magnification

Answer 27

the degree to which the size of an image is larger than the image itself

Question 28

Formula for Light Microscope

Answer 28

eyepiece magnification x objective magnification