B2.3 SL / HL

Question 1

zygote

Answer 1

the single cell that results from the fusion of a sperm cell and an egg cell, forming the first cell of a new individual

Question 2

differentiation

Answer 2

the process by which a cell changes, becoming more specialized and adapted to perform a specific function

Question 3

Embryo

Answer 3

the earliest stage of development for a multicellular organism, specifically during its early stages, usually after fertilization

Question 4

mitosis

Answer 4

a fundamental process in biology where a single cell divides into two identical daughter cells

Question 5

body plan

Answer 5

the basic, fundamental structure or organization of an organism, encompassing its shape, symmetry, and arrangement of tissues and organs

Question 6

Morphogens

Answer 6

signaling molecules that create concentration gradients within a tissue, influencing cell fate and tissue development

Question 7

diffusion

Answer 7

net movement of anything generally from a region of higher concentration to a region of lower concentration

Question 8

Bilateral body plan

Answer 8

an organism where the body has a left and right side that are mirror images of each other along a central axis

Question 9

embryonic stem cells

Answer 9

undifferentiated cells found in the early stages of an embryo’s development

Question 10

meristematic tissue

Answer 10

a plant tissue composed of undifferentiated cells that have the ability to actively divide and differentiate into various specialized plant tissues and organs

Question 11

Indefinite proliferation

Answer 11

the continuous ability of cells to divide and multiply, effectively making them “immortalized” or able to grow indefinitely in culture.This contrasts with normal cells which have a limited lifespan and stop dividing after a certain number of divisions

Question 12

Totipotent

Answer 12

a cell’s ability to differentiate into all the cell types that make up an organism, including the placenta and extra-embryonic tissues

Question 13

unipotent

Answer 13

a stem cell that can only differentiate into one specific type of cell.This type of cell has the lowest potency among stem cells, meaning it is the most limited in its ability to differentiate into other cell types.

Question 14

Self-renewal

Answer 14

the ability of a stem cell to divide and create more stem cells, maintaining the stem cell pool over time

Question 15

Stem cell niches

Answer 15

a tissue compartment that relies upon external signals that modulate the intrinsic cell regulators for self-renewal, proliferation, differentiation, or cell death

Question 16

Bone marrow stem cells

Answer 16

undifferentiated cells within the bone marrow that can develop into various blood cell types, including red blood cells, white blood cells, and platelets

Question 17

Therapeutic cloning

Answer 17

a biological technique used to create stem cells that are genetically identical to a patient’s own cells.These stem cells can then be used to replace damaged or diseased tissues, potentially offering a personalized treatment for conditions like diabetes or paralysis

Question 18

Pluripotent

Answer 18

a cell’s ability to differentiate into most, but not all, cell types of the body

Question 19

Multipotent

Answer 19

stem cells that have the ability to differentiate into a limited number of cell types within a specific lineage

Question 20

Male gametes (sperm cells)

Answer 20

the reproductive cells produced by males that are involved in sexual reproduction

Question 21

Haploid

Answer 21

a cell or organism that has only one complete set of chromosomes

Question 22

Female gametes (egg cells)

Answer 22

reproductive cells produced in the ovaries and contain half the number of chromosomes compared to other body cells, making them haploid

Question 23

Red blood cells (erythrocytes)

Answer 23

the most abundant type of cell in the blood, playing a crucial role in oxygen transport

Question 24

Biconcave shape

Answer 24

describes a structure that is concave (curved inwards) on both sides, like a disc with two indentations on either face.This shape is particularly important in the context of red blood cells (erythrocytes), which have a biconcave disc shape to maximize their surface area for gas exchange

Question 25

Hemoglobin

Answer 25

a protein found in red blood cells responsible for carrying oxygen from the lungs to the body's tissues and organs

Question 26

White blood cells (leukocytes)

Answer 26

the key components of the body's immune system, acting as defenders against infections and diseases. They are produced in the bone marrow and circulate in the blood and lymphatic tissues, where they play a crucial role in recognizing and destroying foreign invaders like bacteria, viruses, and parasites

Question 27

antibodies

Answer 27

proteins produced by the immune system that bind to specific antigens, marking them for destruction

Question 28

chemotaxis

Answer 28

the directed movement of an organism or cell in response to a chemical stimulus, often a gradient of chemical attractants or repellents

Question 29

Amoeboid movement

Answer 29

a type of locomotion where cells or organisms with no fixed shape change their form, typically by extending temporary cytoplasmic projections called pseudopodia

Question 30

Neuron

Answer 30

a specialized cell that transmits electrical and chemical signals throughout the body, enabling communication within the nervous system

Question 31

signal transduction

Answer 31

the process where a cell receives a signal (like a chemical message) and responds to it by changing its behavior or activities

Question 32

receptor cells

Answer 32

specialized cells that detect stimuli and convert them into electrical signals. These signals are then transmitted to other parts of the body, allowing for a response to the detected stimulus

Question 33

interneurons

Answer 33

a type of neuron that primarily function as connectors within the central nervous system. They relay signals between sensory neurons and motor neurons, playing a crucial role in reflexes, neural circuits, and sensory input interpretation

Question 34

Striated muscle fiber

Answer 34

a fundamental unit of striated muscle tissue, characterized by a repeating pattern of light and dark bands called sarcomeres, which give it a striped or "striated" appearance under a microscope

Question 35

neuromuscular junction

Answer 35

a specialized synapse where a motor neuron connects with a muscle fiber, facilitating the transmission of nerve impulses to initiate muscle contraction

Question 36

surface area to volume ratio (SA:V)

Answer 36

the relationship between an object's surface area and its volume. It's a crucial concept in understanding how organisms and cells exchange materials with their environment. A larger SA:V ratio generally means a more efficient rate of exchange, while a smaller ratio can limit the exchange of substances